编译 | 李言
Nature, 6 June 2024, Volume 630 Issue 8015
《自然》2024年6月6日，第630卷，8015期
化学Chemistry
Metals strengthen with increasing temperature at extreme strain rates
在极端应变速率下，金属随温度升高而增强
▲ 作者：Ian Dowding & Christopher A. Schuh
▲ 链接：
https://www.nature.com/articles/s41586-024-07420-1
▲ 摘要：
在此，在应变率大于 106s1且没有冲击合并的情况下进行微弹道冲击测试，我们发现温度升高157°C后，铜的强度增加了约30%，在纯钛和金上也观察到了这种效果。这种效应是违反直觉的，因为正常条件下，几乎所有材料加热时会变软。
这几种纯金属的异常热强化是控制变形机制发生变化的结果，从热激活强化到位错的弹道输运，位错通过声子相互作用经历阻力。研究结果指出了一条从高速制造操作到高超音速运输，能更好建模和预测各种极端应变率条件下材料性能的途径。
▲ Abstract：
Here, with microballistic impact testing at strain rates greater than 106s1, and without shock conflation, we show that the strength of copper increases by about 30% for a 157°C increase in temperature, an effect also observed in pure titanium and gold. This effect is counterintuitive, as almost all materials soften when heated under normal conditions. This anomalous thermal strengthening across several pure metals is the result of a change in the controlling deformation mechanism from thermally activated strengthening to ballistic transport of dislocations, which experience drag through phonon interactions. These results point to a pathway to better model and predict materials properties under various extreme strain rate conditions, from high-speed manufacturing operations to hypersonic transport.
Photocatalytic doping of organic semiconductors
有机半导体的光催化掺杂
▲ 作者：Wenlong Jin, Chi-Yuan Yang et.al
▲ 链接：
https://www.nature.com/articles/s41586-024-07400-5
▲ 摘要：
在此，我们报告了光催化掺杂OSCs，该方法可以在室温下使用空气作为弱氧化剂（p型掺杂）进行操作。这是一种可以应用于各种OSCs和光催化剂的通用方法，产生超过3000 S cm–1的电导率。
我们还展示了成功的光催化还原（n型掺杂），以及同时p型掺杂和n型掺杂的OSCs，其中用于保持电荷中性的有机盐是唯一消耗的化学物质。我们的光催化掺杂方法为推进OSC掺杂和开发下一代有机电子器件提供了巨大的潜力。
▲ Abstract：
Here, we report a previously undescribed concept for the photocatalytic doping of OSCs that uses air as a weak oxidant (p-dopant) and operates at room temperature. This is a general approach that can be applied to various OSCs and photocatalysts, yielding electrical conductivities that exceed 3,000Scm–1. We also demonstrate the successful photocatalytic reduction (n-doping) and simultaneous p-doping and n-doping of OSCs in which the organic salt used to maintain charge neutrality is the only chemical consumed. Our photocatalytic doping method offers great potential for advancing OSC doping and developing next-generation organic electronic devices.
物理学Physics
Dispersion-assisted high-dimensional photodetector
色散辅助高维光电探测器
▲ 作者：Yandong Fan, Weian Huang et.al
▲ 链接：
https://www.nature.com/articles/s41586-024-07398-w
▲ 摘要：
在此，我们证明了具有空间和频率色散的简单薄膜界面可以在波矢量域中投射和定制偏振和频谱响应。通过这种方法，我们可以将高维光信息编码成单次成像，并借助深度残差网络解码。
我们的研究不仅可以通过单一设备和单次测量在宽带频谱上实现任意混合全斯托克斯偏振态的光的全面表征，而且还能提供与最先进的单一用途小型化偏光计或光谱仪相媲美的性能。
▲ Abstract：
Here we demonstrate that simple thin-film interfaces with spatial and frequency dispersion can project and tailor polarization and spectrum responses in the wavevector domain. By this means, high-dimensional light information can be encoded into single-shot imaging and deciphered with the assistance of a deep residual network. To the best of our knowledge, our work not only enables full characterization of light with arbitrarily mixed full-Stokes polarization states across a broadband spectrum with a single device and a single measurement but also presents comparable, if not better, performance than state-of-the-art single-purpose miniaturized polarimeters or spectrometers。
天文学Astronomy
Star formation shut down by multiphase gas outflow in a galaxy at a redshift of 2.45
在一个红移为2.45的星系中，多相气体流出终止了恒星的形成
▲ 作者：Sirio Belli, Minjung Park et.al
▲ 链接：
https://www.nature.com/articles/s41586-024-07412-1
▲ 摘要：
在此，我们报告了在红移2.445处经历快速淬灭的大质量星系的JWST光谱分析结果。我们探测到微弱的电离气体流出和强大的中性气体流出，其质量流出率足以熄灭恒星形成。
我们没有检测到X射线和无线电活动；但是电离气体发射谱线的特性暗示了超大质量黑洞的存在。由此我们认为，超大质量黑洞能够通过有效地喷射中性气体来迅速抑制大质量星系中恒星的形成。
▲ Abstract：
Here we report JWST spectroscopy of a massive galaxy experiencing rapid quenching at a redshift of 2.445. We detect a weak outflow of ionized gas and a powerful outflow of neutral gas, with a mass outflow rate that is sufficient to quench the star formation. Neither X-ray nor radio activity is detected; however, the presence of a supermassive black hole is suggested by the properties of the ionized gas emission lines. We thus conclude that supermassive black holes are able to rapidly suppress star formation in massive galaxies by efficiently ejecting neutral gas.
生物学Biology
Life-cycle-coupled evolution of mitosis in close relatives of animals
动物近缘中有丝分裂的生命周期耦合演化
▲ 作者：Hiral Shah, Marine Olivetta et.al
▲ 链接：
https://www.nature.com/articles/s41586-024-07430-z
▲ 摘要：
在此，我们使用比较基因组学和超微结构成像的综合方法来研究动物和真菌的近亲Ichthyosporea的有丝分裂策略。
我们发现这个分支中的物种已经分化为真菌样的闭合有丝分裂或动物样的开放有丝分裂，可能是为了支持不同的多核或无核状态。我们的研究结果表明，多核生命周期有利于闭合有丝分裂的演化。
▲ Abstract：
Here we use an integrated comparative genomics and ultrastructural imaging approach to investigate mitotic strategies in Ichthyosporea, close relatives of animals and fungi. We show that species in this clade have diverged towards either a fungal-like closed mitosis or an animal-like open mitosis, probably to support distinct multinucleated or uninucleated states. Our results indicate that multinucleated life cycles favour the evolution of closed mitosis.
医学Medicine
A whole-slide foundation model for digital pathology from real-world data
基于真实世界数据的全切片数字病理学模型
▲ 作者：Hanwen Xu, Naoto Usuyama et.al
▲ 链接：
https://www.nature.com/articles/s41586-024-07441-w
▲ 摘要：
在此，我们展示Prov-GigaPath。这是一个全切片病理学基础模型，它对来自美国普罗维顿斯市的171189张全切片中的13亿张256 × 256病理图像进行了预训练。普罗维顿斯市有28个癌症中心。
这些切片来自涵盖31种主要组织类型的3万多名患者。为了预训练Prov-GigaPath，我们提出了一种新的视觉转换器架构GigaPath，用于预训练十亿像素的病理切片。为了将GigaPath扩展到具有数万个图像块的切片级学习，GigaPath将新开发的LongNet方法应用于数字病理学。
为了评估Prov-GigaPath，我们同时使用来自普罗维顿斯市和TCGA数据构建了一个数字病理基准，包括9个癌症亚型任务和17个病理任务。通过大规模预训练和超大上下文建模，Prov-GigaPath在26个任务中的25个任务上达到了最先进的性能，在18个任务上比其他方法有了显著改进。
结合病理报告，我们进一步证明了Prov-GigaPath在病理视觉语言预训练方面的潜力。综上，Prov-GigaPath是一种可在各种数字病理任务中实现最先进的性能的开放权重基础模型，它证明了真实世界数据和全切片建模的重要性。
▲ Abstract：
Here we present Prov-GigaPath, a whole-slide pathology foundation model pretrained on 1.3 billion 256×256 pathology image tiles in 171,189 whole slides from Providence, a large US health network comprising 28 cancer centres. The slides originated from more than 30,000 patients covering 31 major tissue types. To pretrain Prov-GigaPath, we propose GigaPath, a novel vision transformer architecture for pretraining gigapixel pathology slides. To scale GigaPath for slide-level learning with tens of thousands of image tiles, GigaPath adapts the newly developed LongNet method to digital pathology. To evaluate Prov-GigaPath, we construct a digital pathology benchmark comprising 9 cancer subtyping tasks and 17 pathomics tasks, using both Providence and TCGA data. With large-scale pretraining and ultra-large-context modelling, Prov-GigaPath attains state-of-the-art performance on 25 out of 26 tasks, with significant improvement over the second-best method on 18 tasks. We further demonstrate the potential of Prov-GigaPath on vision–language pretraining for pathology by incorporating the pathology reports. In sum, Prov-GigaPath is an open-weight foundation model that achieves state-of-the-art performance on various digital pathology tasks, demonstrating the importance of real-world data and whole-slide modelling.
本文链接：《自然》（20240606出版）一周论文导读http://www.sushuapos.com/show-11-6974-0.html
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