天文学Astronomy Young asteroid families as the primary source of meteorites 年青的小行星族是陨石的首要来历 ▲ 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： 领会敞亮流星和其陨石样本的发源是天文学中最古老的问题之一，在更年夜标准上对人类发生影响。到今朝为止，只有年夜约6%的陨石坠落与其来历（月球、火星或小行星（4）灶神星）有紧密亲密联系关系。 研究组发现年夜约70%的陨石发源在比来产生在580万年前、760万年前和不到4000万年前的三次D 30千米小行星的割裂。这些割裂首要产生在闻名的Karin小行星族、闻名且古老的Koronis小行星族和Massalia小行星族，是H和L通俗球粒陨石在陨石坠落中占主导地位的发源。 这些年青的小行星族在所有主带小行星中都具有怪异的高品貌小碎片。其巨细 频率散布在几万万年内仍连结峻峭，临时跨越了最年夜的古长幼行星族（例如花神星和灶神星）发生的米级碎片。撑持性证据包罗相干尘埃带的存在、H球粒陨石的宇宙射线表露春秋和陨石的年夜气前轨道散布。 ▲ 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通俗L球粒陨石的发源 ▲ 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注解，年夜约4.66亿年前，我们的星球见证了通俗L球粒陨石物资的年夜量坠落，这多是奥陶纪冰河时期和生物多样性重年夜改变的发源。主带中一颗年夜型小行星的解体极可能是此次年夜范围撞击的缘由。今朝，这类解体发生的物资依然主导着陨石坠落（占所有坠落物的20%以上）。 研究组供给了光谱不雅测和动力学证据，注解马萨利亚小行星族碰撞是这场灾害性事务的独一可托来历，也是现今地球上坠落的最丰硕陨石种别。这个小行星族正好位在内带，在低倾角轨道上，这与不雅测到的L 球粒陨石样近地天体和集中在1.4 的行星际尘埃散布相一致。 ▲ 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械进修助力稳健化学阐发 ▲ 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）已成为化学传感利用中不成或缺的东西。ISFETs经由过程将化学溶液构成的转变转换成电旌旗灯号来运行，使其成为情况监测、医疗诊断和工业进程节制的抱负选择。ISFET手艺的最新进展（包罗功能化多路复用阵列和进步前辈数据阐发）提高了其机能。 研究组说明告终合机械进修算法来构建猜测模子的优势，该模子利用ISFET传感器生成的普遍数据集来进行分类和量化使命。这类整合也为ISFET的工作供给了超出人类专业常识的新视角。 另外，该策略还降服了与轮回间、传感器间和芯片间转变相干的现实困难，为ISFET在贸易利用中的普遍采取摊平了道路。具体而言，研究组利用非功能化石墨烯基ISFET阵列生成的数据来练习人工神经收集，这些神经收集具有辨认食物讹诈、食物败北和食物平安问题的出色能力。 研究组估计，紧凑、节能和可反复利用的石墨烯基ISFET手艺与稳健机械进修算法的融会，有可能完全改变邃密化学和情况转变的检测，供给合用在广谱利用的快速、数据驱动的看法。 ▲ 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 可分手镍-烷基共同物的还原烷基-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份子还是有机合成中的一个挑战。已知的反映针对特订婚电试剂进行优化，不合用在常见烷基构建单位（如胺、羧酸和卤化物）发生的可交换转变的亲电底物。这些局限性限制了可被改性的烷基底物类型，并终究限制了可以摸索的化学空间。 研究组报导领会决这些局限性的通用策略，以实现烷基 烷基交叉偶联反映的组合方式。这类方式依靠在发现异常持久的Ni（烷基）共同物，这些共同物可经由过程烷基卤化物、氧化还原活性酯或吡啶鎓盐的氧化加成直接构成。所得烷基共同物可被分手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映。 经由过程脱卤、脱羧或脱胺基偶联的各类组合，氨基酸、自然产品、药物和类药物构建块的快速多样化展现了这类合成能力的适用性。除利用规模普遍外，这项工作还经由过程晶体学阐发、立体化学探针和光谱研究，为合成相干Ni（烷基）共同物的有机金属化学供给了看法。 ▲ 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映 ▲ 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： 氘在有机份子中的掺入在药物化学和材料科学中利用普遍。例如，氘化药物austedo、donafenib和sotyktu比来已获核准。有多种方式可以合成高氘掺入的氘代化合物。但是，芳烃（遍及存在的化学原料）还原氘代至饱和环化合物的方式鲜能实现。 研究组描写了一种可扩大、通用的电催化方式，利用制备的氮搀杂电极和氧化氘（D2O）进行（杂）芳烃的还原性氘代和氘代脱氟，获得全氘代和饱和氘碳产品。该策略已成功利用在13种高氘代药物份子的合成。 机理研究注解，在氮搀杂钌电极存鄙人，由D2O电解发生的钌 氘物种是直接还原芬芳族化合物的要害中心体。这类制备高氘标识表记标帜饱和（杂）环化合物的快速且经济高效的方式可利用在药物开辟和代谢研究。 ▲ 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，年夜气激流对欧洲天气和农业的影响 ▲ 作者：Guobao Xu, Ellie Broadman, Isabel Dorado-Li n, Lara Klippel, Matthew Meko, Ulf B ntgen, et al. ▲链接： https://www.nature.com/articles/s41586-024-07985-x ▲摘要： 年夜气激流是北半球中纬度地域天气转变的主要动力驱动身分。北年夜西洋 欧洲地域夏日激流纬度（EU JSL）位置的现代转变增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变率和其对区域极端天气和社会事务的影响知之甚少，特殊是在报酬变暖之前。 基在三个温度敏感的欧洲树木年轮记实，研究组重建了公元1300~2004年间夏日EU JSL的年际转变（R2= 38.5%），并将其与自力的汗青天气记实和社会记实（如葡萄收获、食粮价钱、瘟疫和人类灭亡率）进行了比力。 研究组展现了公元1300年来与EU JSL变率相干的对照光鲜的夏日极端天气，和生物物理、经济和生齿影响，包罗野火和风行病。按照对激流行动改变和极端天气加重的猜测，该研究成果强调了在评估扩年夜的将来天气风险时斟酌EU JSL变率的主要性。 ▲ 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.特殊声明：本文转载仅仅是出在传布信息的需要，其实不意味着代表本网站不雅点或证实其内容的真实性；如其他媒体、网站或小我从本网站转载利用，须保存本网站注明的“来历”，并自大版权等法令责任；作者假如不但愿被转载或联系转载稿费等事宜，请与我们联系。
