编译|李言

Nature, 18 July 2024, Volume 631 Issue 8021

《自然》2024年7月18日，第631卷，8021期

材料科学Materials Science

Electron holography observation of individual ferrimagnetic lattice planes

单个铁磁晶格面的电子全息观测

▲ 作者：Toshiaki Tanigaki, Tetsuya Akashi et al.

▲链接：

https://www.nature.com/articles/s41586-024-07673-w

▲摘要：

在此，我们报告在无磁场条件下，利用数字后像差校正辅助的硬件型像差校正器以及电子全息技术，观察到具有非均匀结构的材料内部的单个晶格平面的磁场。

我们成功地观察了铁磁性双钙钛矿氧化物（Ba2FeMoO6）中由Fe3+和Mo5+相反自旋顺序形成的(111)晶格面的净磁矩磁相。这一结果为直接观测许多材料和器件中局部区域（如界面和晶界）的磁晶格开辟新途径。

▲ Abstract：

Here we report that the magnetic fields of an individual lattice plane inside materials with a non-uniform structure can be observed under magnetic-field-free conditions by electron holography with a hardware-type aberration corrector assisted by post-digital aberration correction. The magnetic phases of the net magnetic moments of (111) lattice planes formed by opposite spin orderings between Fe3+ and Mo5+ in a ferrimagnetic double-perovskite oxide (Ba2FeMoO6) were successfully observed. This result opens the door to direct observations of the magnetic lattice in local areas, such as interfaces and grain boundaries, in many materials and devices.

工程学Engineering

Sunlight-powered sustained flight of an ultralight micro aerial vehicle

阳光动力持续飞行的超轻微型飞行器

▲ 作者：Wei Shen, Jinzhe Peng et al.

▲链接：

https://www.nature.com/articles/s41586-024-07609-4

▲摘要：

太阳光动力是提高超轻型MAVs续航能力的潜在替代方案，但由于飞行器有限的有效载荷能力，二传统推进系统的升力功率效率较低，以往的研究尚未实现完全由太阳光驱动的MAVs持续飞行。

在此，为了解决这些问题，我们推出静电飞行器CoulombFly，它由30.7 g W-1的高升力—功率效率的静电驱动推进系统和功耗低至0.568 W的超轻千伏电源系统组成，以实现太阳能驱动的MAVs在自然光照条件下（920 W m-2）的持续飞行。

该飞行器的总质量仅为4.21克，仅为现有最轻的太阳能飞行器的1/600。

▲ Abstract：

Sunlight power is a potential alternative to improve the endurance of ultralight MAVs, but owing to the restricted payload capacity of the vehicle and low lift-to-power efficiency of traditional propulsion systems, previous studies have not achieved untethered sustained flight of MAVs fully powered by natural sunlight. Here, to address these challenges, we introduce the CoulombFly, an electrostatic flyer consisting of an electrostatic-driven propulsion system with a high lift-to-power efficiency of 30.7 g W-1 and an ultralight kilovolt power system with a low power consumption of 0.568?W, to realize solar-powered sustained flight of an MAV under natural sunlight conditions (920 W m-2). The vehicle’s total mass is only 4.21?g, within 1/600 of the existing lightest sunlight-powered aerial vehicle.

化学Chemistry

Mechanical release of homogenous proteins from supramolecular gels

超分子凝胶中均质蛋白的机械释放

▲ 作者：Simona Bianco, Muhammad Hasan et al.

▲链接：

https://www.nature.com/articles/s41586-024-07580-0

▲摘要：

在此，我们设计了一种坚硬的水凝胶，即使在50°C下也能稳定蛋白质，防止热变性，并且与现有技术不同，它可以通过从注射器中机械释放出纯的、不含赋形剂的蛋白质。

大分子可以在不影响释放机制的情况下以高达10 wt%的重量加载。这种独特的稳定性和无赋形剂释放协同作用提供了一种实用的、可扩展的和通用的解决方案，使低成本、无冷链和公平的全球治疗交付成为可能。

▲ Abstract：

Here we designed a stiff hydrogel that stabilizes proteins against thermal denaturation even at 50°C, and that can, unlike present technologies, deliver pure, excipient-free protein by mechanically releasing it from a syringe. Macromolecules can be loaded at up to 10wt% without affecting the mechanism of release. This unique stabilization and excipient-free release synergy offers a practical, scalable and versatile solution to enable the low-cost, cold-chain-free and equitable delivery of therapies worldwide.

Chemical reservoir computation in a self-organizing reaction network

自组织反应网络中的化学储层计算

▲ 作者：Mathieu G. Baltussen, Thijs J. de Jong et al.

▲链接：

https://www.nature.com/articles/s41586-024-07567-x

▲摘要：

在此，我们报告一种基于聚糖反应的化学储层计算机。我们展示了这个复杂的、自组织的化学反应网络如何并行地执行几个非线性分类任务，预测其他复杂系统的动态并实现时间序列预测。

这在化学信息处理系统中为复杂化学反应网络的新兴计算能力提供了证明，并为一类新的仿生信息处理系统提供可能。

▲ Abstract：

Here we report on the discovery and implementation of a chemical reservoir computer based on the formose reaction. We demonstrate how this complex, self-organizing chemical reaction network can perform several nonlinear classification tasks in parallel, predict the dynamics of other complex systems and achieve time-series forecasting. This in chemico information processing system provides proof of principle for the emergent computational capabilities of complex chemical reaction networks, paving the way for a new class of biomimetic information processing systems.

生态学Ecology

Human degradation of tropical moist forests is greater than previously estimated

人类对热带潮湿森林的破坏比此前估计的更为严重

▲ 作者：C. Bourgoin, G. Ceccherini et al.

▲链接：

https://www.nature.com/articles/s41586-024-07629-0

▲摘要：

在此，通过将卫星遥感数据与星载光探测和测距（LiDAR）估算的冠层高度和生物量相结合，我们量化了多种类型森林结构退化的程度和持久性。我们估计，由于选择性采伐和火灾，森林高度分别下降了15%和50%，即使在20年后恢复率也很低。

农业和道路扩张导致森林边缘的冠层高度和生物量减少20%至30%，其持续影响甚至可以在森林内1.5公里处测量到。边缘效应侵蚀了剩余热带湿润森林的18%（约206公顷），面积比先前估计的大200%以上。最后，冠层损失超过50%的退化森林更容易被砍伐。

综上，我们的研究呼吁加大努力防止退化和保护已经退化的森林，以实现最近在联合国气候变化和生物多样性会议上作出的承诺。

▲ Abstract：

Here we quantify the magnitude and persistence of multiple types of degradation on forest structure by combining satellite remote sensing data on pantropical moist forest cover changes with estimates of canopy height and biomass from spaceborne light detection and ranging (LiDAR). We estimate that forest height decreases owing to selective logging and fire by 15% and 50%, respectively, with low rates of recovery even after 20 years. Agriculture and road expansion trigger a 20% to 30% reduction in canopy height and biomass at the forest edge, with persistent effects being measurable up to 1.5km inside the forest. Edge effects encroach on 18% (approximately 206 Mha) of the remaining tropical moist forests, an area more than 200% larger than previously estimated. Finally, degraded forests with more than 50% canopy loss are significantly more vulnerable to subsequent deforestation. Collectively, our findings call for greater efforts to prevent degradation and protect already degraded forests to meet the conservation pledges made at recent United Nations Climate Change and Biodiversity conferences.

古生物学Paleontology

Giant stem tetrapod was apex predator in Gondwanan late Palaeozoic ice age

巨型干群四足动物是冈瓦纳晚古生代冰河时期的顶级捕食者

▲ 作者：Claudia A. Marsicano, Jason D. Pardo et al.

▲链接：

https://www.nature.com/articles/s41586-024-07572-0

▲摘要：

在此，我们描述一种来自纳米比亚高古纬度（约南纬55度）早二叠世（约2.8亿年前）沉积物的新的巨型四足动物，Gaiasia jennyae。Gaiasia包括几个大的半联骨骼，其特征是弱骨化的头骨、关节松散的口盖、宽阔的菱形副蝶骨、后凸的枕骨，以及扩大的、交错咬合的齿骨和冠状齿。

系统发育分析表明，在四足动物干群中，Gaiasia是来自欧亚美利加的石炭纪Colosteidae的姊妹类群。Gaiasia比之前描述的所有干群四足动物都要大，它提供的证据表明，在石炭纪—二叠纪冰川消融的最后阶段，大陆四足动物在冈瓦纳寒温带地区已经很好地存在了。

这表明在石炭纪—二叠纪过渡时期，大陆四足动物在全球范围内的分布更为广泛，并且必须重新考虑先前关于全球四足动物更替和分散的假设。

▲ Abstract：

Here we describe a new giant stem tetrapod, Gaiasia jennyae, from high-palaeolatitude (about 55° S) early Permian-aged (about 280?million years ago) deposits in Namibia that challenges this scenario. Gaiasia is represented by several large, semi-articulated skeletons characterized by a weakly ossified skull with a loosely articulated palate dominated by a broad diamond-shaped parasphenoid, a posteriorly projecting occiput, and enlarged, interlocking dentary and coronoid fangs. Phylogenetic analysis resolves Gaiasia within the tetrapod stem group as the sister taxon of the Carboniferous Colosteidae from Euramerica. Gaiasia is larger than all previously described digited stem tetrapods and provides evidence that continental tetrapods were well established in the cold-temperate latitudes of Gondwana during the final phases of the Carboniferous–Permian deglaciation. This points to a more global distribution of continental tetrapods during the Carboniferous–Permian transition and indicates that previous hypotheses of global tetrapod faunal turnover and dispersal at this time2,3 must be reconsidered.