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发布日期：2024-11-21 作者：开云
Nature, 14 November 2024, Volume 635 Issue 8038
《天然》2024年11月14日，第635卷，8038期
天文学Astronomy
Accelerated formation of ultra-massive galaxies in the first billion years
最初10亿年超年夜质量星系的加快构成
▲ 作者：Mengyuan Xiao, Pascal A. Oesch et al.
▲链接：
https://www.nature.com/articles/s41586-024-08094-5
▲摘要：
在此，我们陈述对JWST FRESCO查询拜访中的36个年夜质量尘埃掩蔽星系的系统研究，这些星系的光谱红移在5到9之间。在样本中，我们没有发现Λ 冷暗物资模子具有张力。
但是，三个超年夜质量星系（logM★/M⊙???11.0，此中M★为恒星质量，M⊙为太阳质量）需要50%的重子转化为恒星——比后期最有用的星系高2到3倍。这不太多是由于勾当星系核，由于它们的辐射规模很广。在年夜约5到6的红移规模内，超年夜质量星系占宇宙恒星构成率密度的17%。
▲ Abstract：
Here we report a systematic study of 36 massive dust-obscured galaxies with spectroscopic redshifts between 5 and 9 from the JWST FRESCO survey. We find no tension with the Λ cold dark-matter model in our sample. However, three ultra-massive galaxies (logM★/M⊙???11.0, whereM★ is the stellar mass and M⊙ is the mass of the Sun) require an exceptional fraction of 50 per cent of baryons converted into stars—two to three times higher than the most efficient galaxies at later epochs. The contribution from an active galactic nucleus is unlikely because of their extended emission. Ultra-massive galaxies account for as much as 17 per cent of the total cosmic star-formation-rate density at redshifts between about five and six.
物理学Physics
Observation of vortices in a dipolar supersolid
偶极超固体中涡旋的不雅测
▲ 作者：Eva Casotti, Elena Poli et al.
▲链接：
https://www.nature.com/articles/s41586-024-08149-7
▲摘要：
在此，把握了在偶极气体和具有二维结晶挨次的超固体中发生涡旋的方式后，我们陈述了超固体相（SSP）中涡旋的理论研究和尝试不雅察。我们的工作揭露了未调制和调制量子流体之间涡旋构成动力学的底子差别。
这为研究具有很多存在在分歧范畴——如量子晶体和中子星发——中的自对称性破缺的奇特量子系统的流体动力学特征打开了年夜门。
▲ Abstract：
Here, with the prerequisite pieces at our disposal, namely a method to generate vortices in dipolar gases and supersolids with two-dimensional crystalline order, we report on the theoretical investigation and experimental observation of vortices in the supersolid phase (SSP). Our work reveals a fundamental difference in vortex seeding dynamics between unmodulated and modulated quantum fluids. This opens the door to study the hydrodynamic properties of exotic quantum systems with numerous spontaneously broken symmetries, in disparate domains such as quantum crystals and neutron stars.
Phonon modes and electron–phonon coupling at the FeSe/SrTiO3interface
FeSe/SrTiO3界面处的声子模式和电子—声子耦合
▲ 作者：Hongbin Yang, Yinong Zhou et al.
▲链接：
https://www.nature.com/articles/s41586-024-08118-0
▲摘要：
在此，我们利用动量选择高分辩率电子能量损掉谱，在原子标准上解析FeSe/STO界面上的声子。我们在75—99 meV的能量规模内发现了新的光学声子模式，与电子强耦合。这些模式的特点是界面双层TiOx层中的氧原子和STO中的顶端氧原子的面外振动。
我们的成果还注解，1 uc FeSe/STO的EPC强度和超导间隙与FeSe与TiOx端接STO之间的层间距紧密亲密相干。这些发现揭露了界面EPC的微不雅发源，并为在FeSe/STO和潜伏的其他超导系统中实现年夜范围和不变的Tc加强供给了看法。
▲ Abstract：
Here we use momentum-selective high-resolution electron energy loss spectroscopy to atomically resolve the phonons at the FeSe/STO interface. We uncover new optical phonon modes, coupling strongly with electrons, in the energy range of 75–99 meV. These modes are characterized by out-of-plane vibrations of oxygen atoms in the interfacial double-TiOx layer and the apical oxygens in STO. Our results also demonstrate that the EPC strength and superconducting gap of 1 uc FeSe/STO are closely related to the interlayer spacing between FeSe and the TiOx terminated STO. These findings shed light on the microscopic origin of the interfacial EPC and provide insights into achieving large and consistent Tc enhancement in FeSe/STO and potentially other superconducting systems.
地球科学Earth Science
Mapping the ionosphere with millions of phones
百万部手机绘制电离层“地图”
▲ 作者：Jamie Smith, Anton Kast et al.
▲链接：
https://www.nature.com/articles/s41586-024-08072-x
▲摘要：
在此，我们展现了一个由噪声传感器构成的散布式收集——以数百万部安卓手机的情势——可以弥补很多这些空白，并将丈量笼盖规模扩年夜一倍，活着界上传统根本举措措施办事不足的地域供给电离层的正确图象。
经由过程智妙手机丈量，我们阐发了印度和南美上空的等离子体气泡、北美上空太阳风暴加强的密度和欧洲上空的中纬度电离层槽等特点。我们还注解，由此发生的电离层“地图”可以提高定位精度，这是我们的首要方针。
这项研究展现了利用年夜型散布式智妙手机收集作为监测地球的壮大科学仪器的潜力。
▲ Abstract：
Here we demonstrate that a distributed network of noisy sensors—in the form of millions of Android phones—can fill in many of these gaps and double the measurement coverage, providing an accurate picture of the ionosphere in areas of the world underserved by conventional infrastructure. Using smartphone measurements, we resolve features such as plasma bubbles over India and South America, solar-storm-enhanced density over North America and a mid-latitude ionospheric trough over Europe. We also show that the resulting ionosphere maps can improve location accuracy, which is our primary aim. This work demonstrates the potential of using a large distributed network of smartphones as a powerful scientific instrument for monitoring Earth.
High CO2 dampens then amplifies N-induced diversity loss over 24 years
24年来，高二氧化碳浓度的按捺放年夜了氮引发的多样性损掉
▲ 作者：Peter B. Reich, Neha Mohanbabu et al.
▲链接：
https://www.nature.com/articles/s41586-024-08066-9
▲摘要：
氮沉降致使了全球局部生物多样性的损掉，但二氧化碳浓度的上升是不是会加重或按捺损掉环境，和若何加重或按捺这些损掉，今朝尚不清晰，并且几近完全没有研究过。
经由过程一个露天尝试，我们回覆了这一认知空白。露天尝试中，108块草地在分歧的二氧化碳和氮程度下发展了24年。我们初步发现，增添氮对植物物种丰硕度的下降在二氧化碳浓度升高的环境下比在二氧化碳浓度升高的环境下要小。
但是，跟着时候的推移，这类彼此感化产生了逆转，二氧化碳浓度的升高放年夜了富氮致使的多样性损掉，在曩昔8年的研究中，氮添加致使的物种丰硕度削减了三倍。
这些彼此感化源在多样性驱动身分的时候转变，特别是光有用性，而光有用性又由二氧化碳和氮输入和植物生物量的相干转变驱动。这一机制在很多草地上多是类似的，由于植物质源中二氧化碳和氮的添加可能会增添优势物种的品貌。
假如二氧化碳的上升遍及加重了氮沉降对植物多样性的普遍负面影响，这对全球草地生物多样性的庇护来讲是一个欠好的兆头。
▲ Abstract：
Nitrogen deposition causes local biodiversity loss globally, but whether, and if so how, rising CO2concentrations amplify or dampen those losses remains unclear and is almost entirely unstudied. We addressed this knowledge gap with an open-air experiment in which 108 grassland plots were grown for 24 years under different CO2 and N regimes. We initially found that adding N reduced plant species richness less at elevated than at ambient CO2. Over time, however, this interaction reversed, and elevated CO2 amplified losses in diversity from enriched N, tripling reductions in species richness from N addition over the last eight years of the study. These interactions resulted from temporal changes in the drivers of diversity, especially light availability, that were in turn driven by CO2 and N inputs and associated changes in plant biomass. This mechanism is likely to be similar in many grasslands, because additions of the plant resources CO2 and N are likely to increase the abundance of the dominant species. If rising CO2 generally exacerbates the widespread negative impacts of N deposition on plant diversity, this bodes poorly for the conservation of grassland biodiversity worldwide.
生物学Biology
Inducing novel endosymbioses by implanting bacteria in fungi
经由过程在真菌中植入细菌引诱新的内共生
▲ 作者：Gabriel H. Giger, Chantal Ernst et al.
▲链接：
https://www.nature.com/articles/s41586-024-08010-x
▲摘要：
在此，我们将细菌植入丝状真菌小孢根霉，进行人工引诱的内共生。年夜肠杆菌植入细胞质后可引诱隔阂构成，有用禁止内共生，而根瘤菌则以低频率垂直传布给儿女。
在顺应进化进程中，内共生的延续正向选择将初始顺应度束缚下降了几个数目级。跟着系统的不变，宿主中突变的堆集强调了表型转变。该细菌在其新宿主体内发生了根毒素同系物，证实了经由过程引诱内共生的代谢功能的转移。
是以，单细胞植入供给了一种壮大的尝试方式来研究内共生产生最先时的要害事务，并为设计具有所需性状的内共生的综合方式供给了机遇。
▲ Abstract：
Here we implant bacteria into the filamentous fungus Rhizopus microsporus to follow the fate of artificially induced endosymbioses. Whereas Escherichia coli implanted into the cytosol induced septum formation, effectively halting endosymbiogenesis, Mycetohabitans rhizoxinica was transmitted vertically to the progeny at a low frequency. Continuous positive selection on endosymbiosis mitigated initial fitness constraints by several orders of magnitude upon adaptive evolution. Phenotypic changes were underscored by the accumulation of mutations in the host as the system stabilized. The bacterium produced rhizoxin congeners in its new host, demonstrating the transfer of a metabolic function through induced endosymbiosis. Single-cell implantation thus provides a powerful experimental approach to study critical events at the onset of endosymbiogenesis and opens opportunities for synthetic approaches towards designing endosymbioses with desired traits.
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