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发布日期：2024-07-24 作者：开云
Science,24 MAY 2024, Volume 384 Issue 6698
《科学》2024年5月24日，第384卷，6698期
天文学Astronomy
Strong damped Lyman-α absorption in young star-forming galaxies at redshifts 9 to 11
在红移9到11的年青恒星构成星系中强烈阻尼的莱曼α接收
▲作者：KASPER E. HEINTZ, DARACH WATSON et al.
▲链接：
https://www.science.org/doi/10.1126/science.adj0343
▲摘要：
我们阐发了韦布空间千里镜（JWST）拍摄到的红移为±8的遥远星系的近红外光谱。从包括12个星系的样本中，我们肯定了3个因为其局部情况中的中性原子氢而表示出强烈的阻尼莱曼α接收的星系。
这些星系的光谱红移值别离为8.8、10.2和11.4，对应在宇宙年夜爆炸后的4亿到6亿年。它们的中性原子氢密度≥1022cm?2，这比预期中的中性星系间介质要高一个数目级，而且组成了一个富含气体的年青恒星构成星系群。
▲ Abstract：
We analyzed James Webb Space Telescope (JWST) near-infrared spectroscopy of distant galaxies, at redshifts ?8. From a sample of 12 galaxies, we identified three that show strong damped Lyman-α absorption due to H i in their local surroundings. The galaxies are located at spectroscopic redshifts of 8.8, 10.2, and 11.4, corresponding to 400 to 600 million years after the Big Bang. They have H i column densities ?1022cm?2, which is an order of magnitude higher than expected for a 开云体育appfully neutral intergalactic medium, and constitute a gas-rich population of young star-forming galaxies.
Unrecoverable lattice rotation governs structural degradation of single-crystalline cathodes
不成恢复的晶格扭转节制着单晶阴极的布局退化
▲链接：
https://www.science.org/doi/10.1126/science.ado1675
▲摘要：
操纵多标准空间分辩率衍射和成像手艺，我们不雅察到晶格扭转在单晶阴极中遍及存在，并在布局退化中起要害感化。
这些晶格扭转被证实是不成恢复的，而且在反复的轮回中节制着晦气晶格畸变的堆集，致使布局和机械退化和容量加快阑珊。这些发现填补了之前在快速机能掉效和原子标准布局退化之间的机制联系方面存在的常识差距。
▲ Abstract：
Leveraging multiscale spatial resolution diffraction and imaging techniques, we observe that lattice rotations occur universally in single-crystalline cathodes and play a pivotal role in the structure degradation. These lattice rotations prove unrecoverable and govern the accumulation of adverse lattice distortions over repeated cycles, contributing to structural and mechanical degradation and fast capacity fade. These findings bridge the previous knowledge gap that exists in the mechanistic link between fast performance failure and atomic-scale structure degradation.
Synthesis and characterization of low-dimensional N-heterocyclic carbene lattices
低维氮杂环卡宾晶格的合成与表征
▲链接：
https://www.science.org/doi/10.1126/science.adm9814
▲摘要：
在此，我们展现了一种模块化的方式来设计一维金属有机链和二维Kagome晶格，利用NHC-Au-NHC结的FMOs来建立具有固有金属性的低维份子收集。
扫描地道光谱和第一性道理密度泛函理论揭露了C–Au–C π-键态对具有极小功函数的一维和二维NHC晶格色散带的进献。
▲ Abstract：
Here we demonstrate a modular approach to engineering one-dimensional (1D) metal-organic chains and two-dimensional (2D) Kagome lattices using the FMOs of NHC–Au–NHC junctions to create low-dimensional molecular networks exhibiting intrinsic metallicity. Scanning tunneling spectroscopy and first-principles density functional theory reveal the contribution of C–Au–C π-bonding states to dispersive bands that imbue 1D- and 2D-NHC lattices with exceptionally small work functions.
Impact of early visual experience on later usage of color cues
初期视觉经验对后期色采线索利用的影响
▲作者：MARIN VOGELSANG, LUKAS VOGELSANG et al.
▲链接：
https://www.science.org/doi/10.1126/science.adk9587
▲摘要：
人类的视觉辨认对色彩转变很是敏感。在这项研究中，经由过程对10名先天掉明、后期重获目力的儿童的不雅察，我们对这类恢复力的本源供给了一种潜伏的注释。
在他们的目力恢复手术后的几个月或几年里，色彩线索的移除显著下降了他们的辨认能力，而正常目力的同龄儿童中则没有这类环境。这一发现可以注释为目力恢复儿童在重获目力时的色彩系统比通俗新生儿更成熟，致使对色彩线索的过度依靠。我们用深度神经收集进行的摹拟证实了这一假定。
这些发现凸起了典型发育轨迹的顺应性意义，并为加强机械视觉系统供给了指点。
▲ Abstract：
Human visual recognition is remarkably robust to chromatic changes. In this work, we provide a potential account of the roots of this resilience based on observations with 10 congenitally blind children who gained sight late in life. Several months or years following their sight-restoring surgeries, the removal of color cues markedly reduced their recognition performance, whereas age-matched normally sighted children showed no such decrement. This finding may be explained by the greater-than-neonatal maturity of the late-sighted children’s color system at sight onset, inducing overly strong reliance on chromatic cues. Simulations with deep neural networks corroborate this hypothesis. These findings highlight the adaptive significance of typical developmental trajectories and provide guidelines for enhancing machine vision systems.
Crows “count” the number of self-generated vocalizations
乌鸦会给本身ID啼声“计数”
▲作者：DIANA A. LIAO, KATHARINA F. BRECHT et al.
▲链接：
https://www.science.org/doi/10.1126/science.adl0984
▲摘要：
有目标地发出特定命量的声音需要数字能力和声音节制的复杂连系。除人类以外，动物是不是具有这类能力还不得而知。
我们发现，乌鸦可以矫捷地发出一到四种分歧数目的声音，以响应与数值相干的肆意信息。第一声的声学特点可猜测发声的总次数，注解全部发声进程是有打算的。另外，发声单位的声学特点猜测了它们在的挨次，可用在读动身声进程中的计数毛病。
▲ Abstract：
Producing a specific number of vocalizations with purpose requires a sophisticated combination of numerical abilities and vocal control. Whether this capacity exists in animals other than humans is yet unknown. We show that crows can flexibly produce variable numbers of one to four vocalizations in response to arbitrary cues associated with numerical values. The acoustic features of the first vocalization of a sequence were predictive of the total number of vocalizations, indicating a planning process. Moreover, the acoustic features of vocal units predicted their order in the sequence and could be used to read out counting errors during vocal production.
Rice’s trajectory from wild to domesticated in East Asia
水稻在东亚从野生到驯化的轨迹
▲摘要：
在此，我们供给了从中国长江下流四周的上山和荷花山两个考古遗址中取样的水稻植物化石的证据。我们证实了最少在10万年前就已发展野生稻，它作为一种收集资本的最初开辟年夜约在2.4万年之前，它的前驯化栽种年夜约在1.3万年之前，终究在1.1万年之前完成驯化。
这些成长阶段注解了漫长的东亚水稻驯化进程，并将谷物进化的持续记实延长到新月沃地之外。
▲ Abstract：
Here, we present evidence of rice phytoliths sampled from two archaeological sites in China, Shangshan and Hehuashan, near the lower reaches of the Yangtze River. We demonstrate the growth of wild rice at least 100,000 years before present, its initial exploitation as a gathered resource at about 24,000 years before present, its predomestication cultivation at about 13,000 years before present, and eventually its domestication at about 11,000 years before present. These developmental stages illuminate a protracted process of rice domestication in East Asia and extend the continuous records of cereal evolution beyond the Fertile Crescent.