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天文学Astronomy

The Radcliffe Wave is oscillating

拉德克里夫波在振荡

▲ 作者：Ralf Konietzka, Alyssa A. Goodman et al.

▲ 链接：

https://www.nature.com/articles/s41586-024-07127-3

▲ 摘要：

在此，我们提供的证据表明，拉德克里夫波在穿过银道面振荡的同时，也在从银道中心径向漂移。

我们使用12CO的视距速度测量和年轻星团的3D速度显示在空间上与拉德克利夫波相关的最大规模的恒星形成区域（包括猎户座、仙父座、北美和天鹅座X）的运动，就好像它们是由银河系势能重力加速度驱动的振荡波中的一部分。

通过将拉德克里夫波视为相干振荡结构，我们可以独立于银河系局部质量分布推导出它的运动，并直接测量银河系势的局部性质以及太阳的垂直振荡周期。

此外，我们测量到的拉德克利夫波从银河系中心径向向外的漂移表明，其超新星可能诞生于拉德克利夫波中，由不断膨胀的局部气泡的星团所形成。

▲ Abstract：

Here we present evidence that the Radcliffe Wave is oscillating through the Galactic plane while also drifting radially away from the Galactic Centre. We use measurements of line-of-sight velocity for 12CO and three-dimensional velocities of young stellar clusters to show that the most massive star-forming regions spatially associated with the Radcliffe Wave (including Orion, Cepheus, North America and Cygnus X) move as though they are part of an oscillating wave driven by the gravitational acceleration of the Galactic potential. By treating the Radcliffe Wave as a coherently oscillating structure, we can derive its motion independently of the local Galactic mass distribution, and directly measure local properties of the Galactic potential as well as the Sun’s vertical oscillation period. In addition, the measured drift of the Radcliffe Wave radially outwards from the Galactic Centre suggests that the cluster whose supernovae ultimately created today’s expanding Local Bubble may have been born in the Radcliffe Wave.

物理学Physcis

Rotating curved spacetime signatures from a giant quantum vortex

巨型量子漩涡的旋转弯曲时空特征

▲ 作者：Patrik ?van?ara, Pietro Smaniotto et al.

▲ 链接：

https://www.nature.com/articles/s41586-024-07176-8

▲ 摘要：

在此，我们证实尽管多重量子化涡旋本身具有不稳定性，但静止的巨型量子涡旋却能在超流体4He中保持稳定。它紧凑的核心携带了数千个循环量子，超越了目前其他物理系统（如磁振子、原子云和极化子）的限制。

我们还介绍了一种新颖的、最小侵入式的方法，通过利用超流体界面上微米尺度的波与背景速度场的相互作用，来表征涡旋流动。

我们还观察到复杂的波涡漩相互作用，包括束缚态的检测和独特的模拟黑洞振铃特征。这些研究结果为探索量子到经典的涡旋相变，和使用超流氦作为旋转弯曲时空的有限温度量子场论模拟器开辟了新途径。

▲ Abstract：

Here we demonstrate that, despite the inherent instability of multiply quantized vortices, a stationary giant quantum vortex can be stabilized in superfluid 4He. Its compact core carries thousands of circulation quanta, prevailing over current limitations in other physical systems such as magnons, atomic clouds and polaritons. We introduce a minimally invasive way to characterize the vortex flow by exploiting the interaction of micrometre-scale waves on the superfluid interface with the background velocity field. Intricate wave–vortex interactions, including the detection of bound states and distinctive analogue black hole ringdown signatures, have been observed. These results open new avenues to explore quantum-to-classical vortex transitions and use superfluid helium as a finite-temperature quantum field theory simulator for rotating curved spacetimes.

材料科学Materials Science

Double-side 2D/3D heterojunctions for inverted perovskite solar cells

双面2D/3D异质结的倒置钙钛矿太阳能电池

▲ 作者：Randi Azmi, Drajad Satrio Utomo et al.

▲ 链接：

https://www.nature.com/articles/s41586-024-07189-3

▲ 摘要：

在此，我们证实长烷基胺配体可以在顶部和底部三维钙钛矿界面生成接近相纯的二维钙钛矿。

在后接触侧，我们发现烷基胺配体通过与来自有机空穴运输自组装单层分子的磷酸基的酸碱反应加强了与底层的相互作用，从而得以调节二维钙钛矿的形成过程。

由此，具有双面2D/3D异质结的倒置钙钛矿太阳能电池的功率转换效率达到25.6%，在85度的空气中照射1000小时后，其初始功率转换效率仍能保持在95%。

▲ Abstract：

Here we demonstrate that long alkyl amine ligands can generate near-phase-pure 2D perovskites at the top and bottom 3D perovskite interfaces and effectively resolve these issues. At the rear-contact side, we find that the alkyl amine ligand strengthens the interactions with the substrate through acid–base reactions with the phosphonic acid group from the organic hole-transporting self-assembled monolayer molecule, thus regulating the 2D perovskite formation. With this, inverted perovskite solar cells with double-side 2D/3D heterojunctions achieved a power conversion efficiency of 25.6% (certified 25.0%), retaining 95% of their initial power conversion efficiency after 1,000?h of 1-sun illumination at 85?°C in air.

化学Chemistry

Alkene dialkylation by triple radical sorting

通过三线态自由基烯烃实现的烯烃的双烷基化

▲ 作者：Johnny Z. Wang, William L. Lyon & David W. C. MacMillan

▲ 链接：

https://www.nature.com/articles/s41586-024-07165-x

▲ 摘要：

在此，我们报告使用双分子均溶取代催化在非活化烯烃上对亲电自由基和亲核自由基的分选。这一反应包括原位形成三种不同的自由基，并通过大小和电性来区分，允许区域选择性地形成所需的双烷基化产物。这项研究加速了药学上相关的富含C(sp3)分子的合成，并定义了一种独特的烯烃双烷基化方法。

▲ Abstract：

Here we report the use of bimolecular homolytic substitution catalysis to sort an electrophilic radical and a nucleophilic radical across an unactivated alkene. This reaction involves the in situ formation of three distinct radical species, which are then differentiated by size and electronics, allowing for regioselective formation of the desired dialkylated products. This work accelerates access to pharmaceutically relevant C(sp3)-rich molecules and defines a distinct mechanistic approach for alkene dialkylation.

生物学Biology

The hidden fitness of the male zebra finch courtship song

雄性斑胸草雀求偶之歌的隐蔽适应性

▲ 作者：Danyal Alam, Fayha Zia & Todd F. Roberts

▲ 链接：

https://www.nature.com/articles/s41586-024-07207-4

▲ 摘要：

在此，通过将降维技术应用于斑胸草雀的歌唱行为，我们证明了低维特征空间中的音节传播可以解释单个曲调，是如何作为适应性的忠实指标发挥作用的。

我们发现这种行为的Gestalt测量捕捉到斑胸草雀调音节的谱时独特性：雌性斑胸草雀强烈倾向于占据更多潜在空间的曲调；而在低维空间中匹配路径长度对年轻雄性斑胸草雀来说是很困难的。

我们的研究结果阐明了鸣禽如何进化出简单的曲调，并指出了性选择影响“声乐学习”的不同策略。

▲ Abstract：

Here, by applying dimensionality-reduction techniques to the singing behaviour of zebra finches (Taeniopygia guttata), we show that syllable spread in low-dimensional feature space explains how single songs function as honest indicators of fitness. We find that this Gestalt measure of behaviour captures the spectrotemporal distinctiveness of song syllables in zebra finches; that females strongly prefer songs that occupy more latent space; and that matching path lengths in low-dimensional space is difficult for young males. Our findings clarify how simple vocal repertoires may have evolved in songbirds and indicate divergent strategies for how sexual selection can shape vocal learning.

Collective sensing in electric fish

电鱼的集体感应

▲ 作者：Federico Pedraja & Nathaniel B. Sawtell

▲ 链接：

https://www.nature.com/articles/s41586-024-07157-x

▲ 摘要：

在此，我们提供了来自建模、神经记录和行为实验的证据，证明非洲弱电鱼利用同类的电脉冲来扩大其电定位范围、区分物体和增加信息传输。

这些研究结果为一种集体的新主动感知模式提供了证据。在这种模式中，个体的感知通过附近群体成员的能量释放而增强。

▲ Abstract：

Here we provide evidence from modelling, neural recordings and behavioural experiments that the African weakly electric fish Gnathonemus petersii utilizes the electrical pulses of conspecifics to extend its electrolocation range, discriminate objects and increase information transmission. These results provide evidence for a new, collective mode of active sensing in which individual perception is enhanced by the energy emissions of nearby group members.