編譯 | 李言
Nature, 4 April 2024, Volume 628 Issue 8006
《自然》2024年4月4日，第628卷，8006期
天文學Astronomy
The Radcliffe Wave is oscillating
拉德克里夫波在振蕩
▲ 作者：Ralf Konietzka, Alyssa A. Goodman et al.
▲ 鏈接：
https://www.nature.com/articles/s41586-024-07127-3
▲ 摘要：
在此，我們提供的證據表明，拉德克里夫波在穿過銀道面振蕩的同時，也在從銀道中心徑向漂移。
我們使用12CO的視距速度測量和年輕星團的3D速度顯示在空間上與拉德克利夫波相關的最大規模的恒星形成區域（包括獵戶座、仙父座、北美和天鵝座X）的運動，就好像它們是由銀河系勢能重力加速度驅動的振蕩波中的一部分。
通過將拉德克里夫波視為相干振蕩結構，我們可以獨立于銀河系局部質量分布推導出它的運動，并直接測量銀河系勢的局部性質以及太陽的垂直振蕩周期。
此外，我們測量到的拉德克利夫波從銀河系中心徑向向外的漂移表明，其超新星可能誕生于拉德克利夫波中，由不斷膨脹的局部氣泡的星團所形成。
▲ 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.
物理學Physcis
Rotating curved spacetime signatures from a giant quantum vortex
巨型量子漩渦的旋轉彎曲時空特征
▲ 作者：Patrik ?van?ara, Pietro Smaniotto et al.
▲ 鏈接：
https://www.nature.com/articles/s41586-024-07176-8
▲ 摘要：
在此，我們證實盡管多重量子化渦旋本身具有不穩定性，但靜止的巨型量子渦旋卻能在超流體4He中保持穩定。它緊湊的核心攜帶了數千個循環量子，超越了目前其他物理系統（如磁振子、原子云和極化子）的限制。
我們還介紹了一種新穎的、最小侵入式的方法，通過利用超流體界面上微米尺度的波與背景速度場的相互作用，來表征渦旋流動。
我們還觀察到復雜的波渦漩相互作用，包括束縛態的檢測和獨特的模擬黑洞振鈴特征。這些研究結果為探索量子到經典的渦旋相變，和使用超流氦作為旋轉彎曲時空的有限溫度量子場論模擬器開辟了新途徑。
▲ 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.
材料科學Materials Science
Double-side 2D/3D heterojunctions for inverted perovskite solar cells
雙面2D/3D異質結的倒置鈣鈦礦太陽能電池
▲ 作者：Randi Azmi, Drajad Satrio Utomo et al.
▲ 鏈接：
https://www.nature.com/articles/s41586-024-07189-3
▲ 摘要：
在此，我們證實長烷基胺配體可以在頂部和底部三維鈣鈦礦界面生成接近相純的二維鈣鈦礦。
在后接觸側，我們發現烷基胺配體通過與來自有機空穴運輸自組裝單層分子的磷酸基的酸堿反應加強了與底層的相互作用，從而得以調節二維鈣鈦礦的形成過程。
由此，具有雙面2D/3D異質結的倒置鈣鈦礦太陽能電池的功率轉換效率達到25.6%，在85度的空氣中照射1000小時后，其初始功率轉換效率仍能保持在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.
化學Chemistry
Alkene dialkylation by triple radical sorting
通過三線態自由基烯烴實現的烯烴的雙烷基化
▲ 作者：Johnny Z. Wang, William L. Lyon & David W. C. MacMillan
▲ 鏈接：
https://www.nature.com/articles/s41586-024-07165-x
▲ 摘要：
在此，我們報告使用雙分子均溶取代催化在非活化烯烴上對親電自由基和親核自由基的分選。這一反應包括原位形成三種不同的自由基，并通過大小和電性來區分，允許區域選擇性地形成所需的雙烷基化產物。這項研究加速了藥學上相關的富含C(sp3)分子的合成，并定義了一種獨特的烯烴雙烷基化方法。
▲ 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.
生物學Biology
The hidden fitness of the male zebra finch courtship song
雄性斑胸草雀求偶之歌的隱蔽適應性
▲ 作者：Danyal Alam, Fayha Zia & Todd F. Roberts
▲ 鏈接：
https://www.nature.com/articles/s41586-024-07207-4
▲ 摘要：
在此，通過將降維技術應用于斑胸草雀的歌唱行為，我們證明了低維特征空間中的音節傳播可以解釋單個曲調，是如何作為適應性的忠實指標發揮作用的。
我們發現這種行為的Gestalt測量捕捉到斑胸草雀調音節的譜時獨特性：雌性斑胸草雀強烈傾向于占據更多潛在空間的曲調；而在低維空間中匹配路徑長度對年輕雄性斑胸草雀來說是很困難的。
我們的研究結果闡明了鳴禽如何進化出簡單的曲調，并指出了性選擇影響“聲樂學習”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
電魚的集體感應
▲ 作者：Federico Pedraja & Nathaniel B. Sawtell
▲ 鏈接：
https://www.nature.com/articles/s41586-024-07157-x
▲ 摘要：
在此，我們提供了來自建模、神經記錄和行為實驗的證據，證明非洲弱電魚利用同類的電脈沖來擴大其電定位范圍、區分物體和增加信息傳輸。
這些研究結果為一種集體的新主動感知模式提供了證據。在這種模式中，個體的感知通過附近群體成員的能量釋放而增強。
▲ 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.
本文鏈接：《自然》（20240404出版）一周論文導讀http://m.sq15.cn/show-11-4672-0.html
聲明：本網站為非營利性網站，本網頁內容由互聯網博主自發貢獻，不代表本站觀點，本站不承擔任何法律責任。天上不會到餡餅，請大家謹防詐騙！若有侵權等問題請及時與本網聯系，我們將在第一時間刪除處理。
上一篇： “迷你肝臟”療法開展人體試驗
下一篇： 港大研究指高香草酸有助緩解抑郁癥