《自然》（20240912出版）一周論文導讀

物理學Physics

▲ 作者：Wouter Vlemmings, Theo Khouri, Behzad Bojnordi Arbab, Elvire De Beck & Matthias Maercker

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07836-9

▲ 摘要：

在恒星演化的許多階段，能量的對流傳輸都很重要，這在太陽或巨大的演化恒星中已經得到了很好的研究。在大質量紅超巨星的表面也發現了對流的特征。同樣，對于低質量演化的恒星，也發現了對流的跡象，但對流的時間尺度和大小仍然沒有得到很好的限制。

模型表明，對流運動對于產生強風至關重要，強風使恒星核合成的產物返回到星際介質中。研究者報告了一系列重建的干涉測量圖像的表面演變的巨星R劍魚座。這些圖像揭示了一個具有突出的小尺度特征的星盤，它提供了恒星表面對流的結構和運動。

他們發現恒星盤上特征的主導結構尺寸為0.72±0.05天文單位。他們測量到地表運動的速度在- 18和+20 km s - 1之間變化，這意味著對流的時間尺度大約是一個月。這表明低質量和高質量演化恒星的對流特性之間可能存在差異。

▲ Abstract：

The transport of energy through convection is important during many stages of stellar evolution, and is best studied in our Sun or giant evolved stars. Features that are attributed to convection are found on the surface of massive red supergiant stars. Also for lower-mass evolved stars, indications of convection are found, but convective timescales and sizes remain poorly constrained. Models indicate that convective motions are crucial to produce strong winds that return the products of stellar nucleosynthesis into the interstellar medium. Here we report a series of reconstructed interferometric images of the surface of the evolved giant star R?Doradus. The images reveal a stellar disk with prominent small-scale features that provide the structure and motions of convection on the stellar surface. We find that the dominant structure size of the features on the stellar disk is 0.72?±?0.05 astronomical units. We measure the velocity of the surface motions to vary between ?18 and +20?km?s?1, which means that the convective timescale is approximately one month. This indicates a possible difference between the convection properties of low-mass and high-mass evolved stars.

▲ 作者：Stefano Carniani, Kevin Hainline, Francesco D’Eugenio, Daniel J. Eisenstein, Peter Jakobsen, Joris Witstok, Benjamin D. Johnson, Jacopo Chevallard, Roberto Maiolino, Jakob M. Helton, Chris Willott, Brant Robertson, Stacey Alberts, Santiago Arribas, William M. Baker, Rachana Bhatawdekar, Kristan Boyett, Andrew J. Bunker, Alex J. Cameron, Phillip A. Cargile, Stéphane Charlot, Mirko Curti, Emma Curtis-Lake, Eiichi Egami, Christopher N. A. Willmer Show authors

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07860-9

▲ 摘要：

詹姆斯·韋布太空望遠鏡首次觀測的紅移為z≈13的星系，徹底改變了人們對宇宙的理解。此外，“黎明”號探測器發現的許多發光星系（z >10）表明，星系發展迅速，與許多標準模型存在明顯的張力。然而，這些星系大多缺乏光譜確認，因此它們的距離和性質是不確定的。

研究者展示了韋布先進深河外巡天—近紅外光譜儀對兩個發光星系在和z = 13.90±0.17處的光譜確認。光譜顯示紫外連續帶明顯的萊曼α斷裂，但沒有探測到發射線。

這一發現證明，在宇宙大爆炸后3億年，發光星系就已經存在了，而且比在韋布之前預期的要普遍得多。這兩個星系中最遙遠的那個出乎意料地明亮，其空間分辨半徑為260秒差距。再考慮到第二個星系非常陡峭的紫外線斜率，研究者認為，這兩個星系都是由恒星連續輻射主導的，這表明早期宇宙中發光星系的過剩不能完全用黑洞的吸積來解釋。星系形成模型需要解決在宇宙歷史的早期存在如此巨大和明亮的星系的問題。

▲ Abstract：

The first observations of the James Webb Space Telescope (JWST) have revolutionized our understanding of the Universe by identifying galaxies at redshift z?≈?13 . In addition, the discovery of many luminous galaxies at Cosmic Dawn (z?>?10) has suggested that galaxies developed rapidly, in apparent tension with many standard models. However, most of these galaxies lack spectroscopic confirmation, so their distances and properties are uncertain. Here we present JWST Advanced Deep Extragalactic Survey–Near-Infrared Spectrograph spectroscopic confirmation of two luminous galaxies at  and z?=?13.90?±?0.17. The spectra reveal ultraviolet continua with prominent Lyman-α breaks but no detected emission lines. This discovery proves that luminous galaxies were already in place 300?million years after the Big Bang and are more common than what was expected before JWST. The most distant of the two galaxies is unexpectedly luminous and is spatially resolved with a radius of 260?parsecs. Considering also the very steep ultraviolet slope of the second galaxy, we conclude that both are dominated by stellar continuum emission, showing that the excess of luminous galaxies in the early Universe cannot be entirely explained by accretion onto black holes. Galaxy formation models will need to address the existence of such large and luminous galaxies so early in cosmic history.

▲ 作者：Jr-Chiun Yu, Shaurya Bhave, Lee Reeve, Bo Song & Ulrich Schneider

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07875-2

▲ 摘要：

無序的存在實質上影響了物理系統的行為。它可以引起慢動力學或玻璃動力學，或完全抑制輸運，如在安德森絕緣體中，通常擴展的波函數，如光場或電子布洛赫波變得指數局域化。無序和相互作用的綜合效應是豐富的凝聚態物理的核心。

在玻色子系統中，它也可以導致額外的量子態，如玻色玻璃——一種在無序玻色子系統中出現的沒有長程相相干的絕緣但可壓縮的狀態，與眾所周知的相互作用玻色子的超流體和莫特絕緣基態不同。研究者報道了在八重對稱準晶體光學晶格中使用超冷原子的二維玻色玻璃的實驗實現。通過探測系統的相干性，他們觀察到玻色玻璃到超流體的轉變，并繪制了弱相互作用狀態下的相圖。

研究進一步證明了在典型的實驗時間尺度上不可能絕熱穿越玻色玻璃，通過檢查恢復相干性的能力，并討論了與玻色玻璃預期的非遍歷性的聯系。該觀察結果與最近的量子蒙特卡羅預測非常吻合，為實驗測試玻色玻璃、多體局域化和玻璃動力學之間的聯系鋪平了道路。

▲ Abstract：

The presence of disorder substantially influences the behaviour of physical systems. It can give rise to slow or glassy dynamics, or to a complete suppression of transport as in Anderson insulators, where normally extended wavefunctions such as light fields or electronic Bloch waves become exponentially localized. The combined effect of disorder and interactions is central to the richness of condensed-matter physics. In bosonic systems, it can also lead to additional quantum states such as the Bose glass—an insulating but compressible state without long-range phase coherence that emerges in disordered bosonic systems and is distinct from the well-known superfluid and Mott insulating ground states of interacting bosons. Here we report the experimental realization of the two-dimensional Bose glass using ultracold atoms in an eight-fold symmetric quasicrystalline optical lattice. By probing the coherence properties of the system, we observe a Bose-glass-to-superfluid transition and map out the phase diagram in the weakly interacting regime. We furthermore demonstrate that it is not possible to adiabatically traverse the Bose glass on typical experimental timescales by examining the capability to restore coherence and discuss the connection to the expected non-ergodicity of the Bose glass. Our observations are in good agreement with recent quantum Monte Carlo predictions6 and pave the way for experimentally testing the connection between the Bose glass, many-body localization and glassy dynamics more generally.

生物學和古人類學

Biology & Paleoanthropology

▲ 作者：Jianwei Chen, Yangyang Jia, Ying Sun, Kun Liu, Changhao Zhou, Chuan Liu, Denghui Li, Guilin Liu, Chengsong Zhang, Tao Yang, Lei Huang, Yunyun Zhuang, Dazhi Wang, Dayou Xu, Qiaoling Zhong, Yang Guo, Anduo Li, Inge Seim, Ling Jiang, Lushan Wang, Simon Ming Yuen Lee, Yujing Liu, Dantong Wang, Guoqiang Zhang,Guangyi Fan Show authors

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07891-2

▲ 摘要：

過去二十年，從海洋系統中檢索到的微生物基因組數量顯著增加。然而，將這種海洋基因組多樣性轉化為生物技術和生物醫學應用仍然具有挑戰性。研究者從公開的海洋宏基因組中恢復了43191個細菌和古細菌基因組，包括138個不同門的廣泛多樣性，重新定義了海洋細菌基因組大小的上限，并揭示了基因編輯CRISPR-Cas系統和抗生素抗性基因之間的復雜權衡。

對這些海洋基因組的硅生物勘探導致發現了一種新的CRISPR-Cas9系統，10種抗菌肽和3種降解聚對苯二甲酸乙二醇酯的酶。體外實驗證實了其有效性和療效。這項工作證明，全球規模的測序計劃促進了人們對微生物多樣性如何在海洋中進化和維持的理解，并證明了如何可持續地利用這些計劃來推進生物技術和生物醫學。

▲ Abstract：

The past two decades has witnessed a remarkable increase in the number of microbial genomes retrieved from marine systems. However, it has remained challenging to translate this marine genomic diversity into biotechnological and biomedical applications. Here we recovered 43,191 bacterial and archaeal genomes from publicly available marine metagenomes, encompassing a wide range of diversity with 138 distinct phyla, redefining the upper limit of marine bacterial genome size and revealing complex trade-offs between the occurrence of CRISPR–Cas systems and antibiotic resistance genes. In silico bioprospecting of these marine genomes led to the discovery of a novel CRISPR–Cas9 system, ten antimicrobial peptides, and three enzymes that degrade polyethylene terephthalate. In vitro experiments confirmed their effectiveness and efficacy. This work provides evidence that global-scale sequencing initiatives advance our understanding of how microbial diversity has evolved in the oceans and is maintained, and demonstrates how such initiatives can be sustainably exploited to advance biotechnology and biomedicine.

▲ 作者：J. Víctor Moreno-Mayar, Bárbara Sousa da Mota, Tom Higham, Signe Klemm, Moana Gorman Edmunds, Jesper Stenderup, Miren Iraeta-Orbegozo, Véronique Laborde, Evelyne Heyer, Francisco Torres Hochstetter, Martin Friess, Morten E. Allentoft, Hannes Schroeder, Olivier Delaneau & Anna-Sapfo Malaspinas

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07881-4

▲ 摘要：

拉帕努伊島（也被稱為復活節島）是世界上最孤立的有人居住的地方之一。它的考古記錄吸引了許多人的想象力，其中包括被稱為“摩艾”的標志性巨石雕像。對拉帕努伊島的廣泛研究產生了兩個突出的爭論。

首先，拉帕努伊人的歷史被描述為一個資源過度開發的警告故事，最終導致了人口的大規模崩潰——“生態滅絕”理論。其次，在與歐洲人接觸之前，跨太平洋航行到美洲的可能性仍然存在爭議。

為了解決這些爭議，研究者基于15個古老的拉帕努伊人個體重建了拉帕努伊人的基因組歷史。他們對這些個體進行了放射性碳測定和全基因組測序，發現這些人來自波利尼西亞人，與現在的拉帕努伊人關系最密切。通過有效的種群規模重建和廣泛的種群遺傳學模擬，研究者否定了生態滅絕理論提出的17世紀嚴重種群瓶頸的情景。

此外，古代和現在的拉帕努伊人攜帶著相似比例的美洲原住民混合物（約10%）。利用貝葉斯方法綜合遺傳和放射性碳年代，他們估計這一混合事件發生在公元1250~1430年。

▲ Abstract：

Rapa Nui (also known as Easter Island) is one of the most isolated inhabited places in the world. It has captured the imagination of many owing to its archaeological record, which includes iconic megalithic statues called moai. Two prominent contentions have arisen from the extensive study of Rapa Nui. First, the history of the Rapanui has been presented as a warning tale of resource overexploitation that would have culminated in a major population collapse—the ‘ecocide’ theory. Second, the possibility of trans-Pacific voyages to the Americas pre-dating European contact is still debated. Here, to address these questions, we reconstructed the genomic history of the Rapanui on the basis of 15 ancient Rapanui individuals that we radiocarbon dated (1670–1950?CE) and whole-genome sequenced (0.4–25.6×). We find that these individuals are Polynesian in origin and most closely related to present-day Rapanui, a finding that will contribute to repatriation efforts. Through effective population size reconstructions and extensive population genetics simulations, we reject a scenario involving a severe population bottleneck during the 1600s, as proposed by the ecocide theory. Furthermore, the ancient and present-day Rapanui carry similar proportions of Native American admixture (about 10%). Using a Bayesian approach integrating genetic and radiocarbon dates, we estimate that this admixture event occurred about 1250–1430?CE.

人工智能 Artificial intelligence

▲ 作者：Nicholas H. Angello, David M. Friday, Changhyun Hwang, Seungjoo Yi, Austin H. Cheng, Tiara C. Torres-Flores, Edward R. Jira, Wesley Wang, Alán Aspuru-Guzik, Martin D. Burke, Charles M. Schroeder, Ying Diao & Nicholas E. Jackson

▲ 鏈接：

https://www.nature.com/articles/s41586-024-07892-1

▲ 摘要：

人工智能引導的閉環實驗已經成為優化目標函數的一種很有前途的方法，但這種傳統的黑箱方法在發現新化學知識方面的巨大潛力仍未得到很大程度的開發。研究者報告了閉環實驗與基于物理的特征選擇和監督學習的集成，稱為閉環轉移（CLT），以產生與目標函數優化并行的化學見解。

CLT用于研究各種有機電子應用中使用的光收集供體—受體分子溶液中的光穩定性因素，并顯示了包括三重態流形的高能區域的重要性在內的基本見解。這是可能的自動化模塊化合成和實驗表征，只有大約1.5%的理論化學空間。通過多個實驗測試集，并通過調整溶劑的三重態激發態能量，在閉環光穩定性優化過程中突破觀察到的平臺，驗證了該物理信息模型的光穩定性。

CLT在其他材料系統中的進一步應用支持了該策略在增強閉環策略中的推廣。總的來說，這些發現表明，將可解釋的監督學習模型和基于物理的特征與閉環發現過程相結合，可以快速提供基本的化學見解。

▲ Abstract：

Artificial intelligence-guided closed-loop experimentation has emerged as a promising method for optimization of objective functions, but the substantial potential of this traditionally black-box approach to uncovering new chemical knowledge has remained largely untapped. Here we report the integration of closed-loop experiments with physics-based feature selection and supervised learning, denoted as closed-loop transfer (CLT), to yield chemical insights in parallel with optimization of objective functions. CLT was used to examine the factors dictating the photostability in solution of light-harvesting donor–acceptor molecules used in a variety of organic electronics applications, and showed fundamental insights including the importance of high-energy regions of the triplet state manifold. This was possible following automated modular synthesis and experimental characterization of only around 1.5% of the theoretical chemical space. This physics-informed model for photostability was strengthened using multiple experimental test sets and validated by tuning the triplet excited-state energy of the solvent to break out of the observed plateau in the closed-loop photostability optimization process. Further applications of CLT to additional materials systems support the generalizability of this strategy for augmenting closed-loop strategies. Broadly, these findings show that combining interpretable supervised learning models and physics-based features with closed-loop discovery processes can rapidly provide fundamental chemical insights.