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发布日期：2024-09-10 作者：开云
Nature, 18 July 2024, Volume 631 Issue 8021
《天然》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不雅测
▲ 作者：Toshiaki Tanigaki, Tetsuya Akashi et al.
▲链接：
https://www.nature.com/articles/s41586-024-07673-w
▲摘要：
在此，我们陈述在无磁场前提下，操纵数字后像差校订辅助的硬件型像差校订器和电子全息手艺，不雅察到具有非平均布局的材料内部的单个晶格平面的磁场。
我们成功地不雅察了铁磁性双钙钛矿氧化物（Ba2FeMoO6）中由Fe3+和Mo5+相反自旋挨次构成的(111)晶格面的净磁矩磁相。这一成果为直接不雅测很多材料和器件中局部区域（如界面和晶界）的磁晶格斥地新路子。
▲ 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
阳光动力延续飞翔的超稍微型飞翔器
▲ 作者：Wei Shen, Jinzhe Peng et al.
▲链接：
https://www.nature.com/articles/s41586-024-07609-4
▲摘要：
太阳光动力是提崇高高贵轻型MAVs续航能力的潜伏替换方案，但因为飞翔器有限的有用载荷能力，二传统推动系统的升力功率效力较低，以往的研究还没有实现完全由太阳光驱动的MAVs延续飞翔。
在此，为领会决这些问题，我们推出静电飞翔器CoulombFly，它由30.7 g W-1的高升力—功率效力的静电驱动推动系统和功耗低至0.568 W的超轻千伏电源系统构成，以实现太阳能驱动的MAVs在天然光照前提下（920 W m-2）的延续飞翔。
该飞翔器的总质量仅为4.21克，仅为现有最轻的太阳能飞翔器的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
超份子凝胶中均质卵白的机械释放
▲ 作者：Simona Bianco, Muhammad Hasan et al.
▲链接：
https://www.nature.com/artic开云体育apples/s41586-024-07580-0
▲摘要：
在此，我们设计了一种坚固的水凝胶，即便在50°C下也能不变卵白质，避免热变性，而且与现有手艺分歧，它可以经由过程从打针器中机械释放出纯的、不含赋形剂的卵白质。
年夜份子可以在不影响释放机制的环境下以高达10 wt%的重量加载。这类怪异的不变性和无赋形剂释放协同感化供给了一种适用的、可扩大的和通用的解决方案，使低本钱、无冷链和公允的全球医治交付成为可能。
▲ 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
自组织反映收集中的化学储层计较
▲ 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，我们陈述一种基在聚糖反映的化学储层计较机。我们展现了这个复杂的、自组织的化学反映收集若何并行地履行几个非线性分类使命，猜测其他复杂系统的动态并实现时候序列猜测。
这在化学信息处置系统中为复杂化学反映收集的新兴计较能力供给了证实，并为一类新的仿生信息处置系统供给可能。
▲ 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
人类对热带湿润丛林的粉碎比此前估量的更加严重
▲ 作者：C. Bourgoin, G. Ceccherini et al.
▲链接：
https://www.nature.com/articles/s41586-024-07629-0
▲摘要：
在此，经由过程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连系，我们量化了多种类型丛林布局退化的水平和持久性。我们估量，因为选择性采伐和火警，丛林高度别离降落了15%和50%，即便在20年后恢复率也很低。
农业和道路扩大致使丛林边沿的冠层高度和生物量削减20%至30%，其延续影响乃至可以在丛林内1.5千米处丈量到。边沿效应腐蚀了残剩热带潮湿丛林的18%（约206公顷），面积比先前估量的年夜200%以上。最后，冠层损掉跨越50%的退化丛林更轻易被砍伐。
综上，我们的研究呼吁加年夜尽力避免退化和庇护已退化的丛林，以实现比来在结合国天气转变和生物多样性会议上作出的许诺。
▲ 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期间的顶级捕食者
▲ 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，我们描写一种来自纳米比亚古雅纬度（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包罗几个年夜的半联骨骼，其特点是弱骨化的头骨、关节疏松的口盖、宽广的菱形副蝶骨、后凸的枕骨，和扩年夜的、交织咬合的齿骨和冠状齿。
系统发育阐发注解，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比之前描写的所有干群四足动物都要年夜，它供给的证据注解，在石炭纪—二叠纪冰川消融的最后阶段，年夜陆四足动物在冈瓦纳寒温带地域已很好地存在了。
这注解在石炭纪—二叠纪过渡期间，年夜陆四足动物在全球规模内的散布更加普遍，而且必需从头斟酌先前关在全球四足动物更替和分离的假定。
▲ 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.
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