作者:李言 来源:科学网微信公众号 发布时间:2024/5/26 20:47:27
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《科学》(20240524出版)一周论文导读

 

Science,  24 MAY 2024, Volume 384 Issue 6698

《科学》2024年5月24日,第384卷,6698期

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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的年轻恒星形成星系中强烈阻尼的莱曼α吸收

▲ 作者:KASPER E. HEINTZ, DARACH WATSON et al.

▲ 链接:

https://www.science.org/doi/10.1126/science.adj0343


▲ 摘要:

我们分析了韦布空间望远镜(JWST)拍摄到的红移为±8的遥远星系的近红外光谱。从包含12个星系的样本中,我们确定了3个由于其局部环境中的中性原子氢而表现出强烈的阻尼莱曼α吸收的星系。


这些星系的光谱红移值分别为8.8、10.2和11.4,对应于宇宙大爆炸后的4亿到6亿年。它们的中性原子氢密度≥1022 cm?2,这比预期中的中性星系间介质要高一个数量级,并且构成了一个富含气体的年轻恒星形成星系群。


▲ 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 ?1022 cm?2, which is an order of magnitude higher than expected for a fully neutral intergalactic medium, and constitute a gas-rich population of young star-forming galaxies.


材料科学Materials Science


Unrecoverable lattice rotation governs structural degradation of single-crystalline cathodes

不可恢复的晶格旋转控制着单晶阴极的结构退化

▲ 作者:WEIYUAN HUANG, TONGCHAO LIU et al.

▲ 链接:

https://www.science.org/doi/10.1126/science.ado1675


▲ 摘要:

利用多尺度空间分辨率衍射和成像技术,我们观察到晶格旋转在单晶阴极中普遍存在,并在结构退化中起关键作用。


这些晶格旋转被证明是不可恢复的,并且在重复的循环中控制着不利晶格畸变的积累,导致结构和机械退化以及容量加速衰退。这些发现弥补了之前在快速性能失效和原子尺度结构退化之间的机制联系方面存在的知识差距。


▲ 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

▲ 作者:BOYU QIE, ZIYI WANG et al.

▲ 链接:

https://www.science.org/doi/10.1126/science.adm9814


▲ 摘要:

在此,我们展示了一种模块化的方法来设计一维金属有机链和二维Kagome晶格,使用NHC-Au-NHC结的FMOs来创建具有固有金属性的低维分子网络。


扫描隧道光谱和第一性原理密度泛函理论揭示了C–Au–C π-键态对具有极小功函数的一维和二维NHC晶格色散带的贡献。


▲ 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.


医学Medicine


Impact of early visual experience on later usage of color cues

早期视觉经验对后期色彩线索使用的影响

▲ 作者:MARIN VOGELSANG, LUKAS VOGELSANG et al.

▲ 链接:

https://www.science.org/doi/10.1126/science.adk9587


▲ 摘要:

人类的视觉识别对颜色变化非常敏感。在这项研究中,通过对10名先天失明、后期重获视力的儿童的观察,我们对这种恢复力的根源提供了一种潜在的解释。


在他们的视力恢复手术后的几个月或几年里,颜色线索的移除显著降低了他们的识别能力,而正常视力的同龄儿童中则没有这种情况。这一发现可以解释为视力恢复儿童在重获视力时的颜色系统比普通新生儿更成熟,导致对颜色线索的过度依赖。我们用深度神经网络进行的模拟证实了这一假设。


这些发现突出了典型发育轨迹的适应性意义,并为增强机器视觉系统提供了指导。


▲ 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.


生物学Biology


Crows “count” the number of self-generated vocalizations

乌鸦会给自己ID叫声“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:

有目的地发出特定数量的声音需要数字能力和声音控制的复杂结合。除人类之外,动物是否具备这种能力还不得而知。


我们发现,乌鸦可以灵活地发出一到四种不同数量的声音,以响应与数值相关的任意信息。第一声的声学特征可预测发声的总次数,表明整个发声过程是有计划的。此外,发声单元的声学特征预测了它们在的顺序,可用于读出发声过程中的计数错误。


▲ 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.


古植物学Paleobotany


Rice’s trajectory from wild to domesticated in East Asia

水稻在东亚从野生到驯化的轨迹

▲ 作者:JIANPING ZHANG, LEPING JIANG et al.

▲ 链接:

https://www.science.org/doi/10.1126/science.ade4487


▲ 摘要:

在此,我们提供了从中国长江下游附近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。我们证明了至少在10万年前就已生长野生稻,它作为一种采集资源的最初开发大约在2.4万年之前,它的前驯化栽种大约在1.3万年之前,最终在1.1万年之前完成驯化。


这些发展阶段表明了漫长的东亚水稻驯化过程,并将谷物进化的连续记录延伸到新月沃地以外。


▲ 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.

 
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