▲ 作者：YUNJIE LI, GUO YUAN, LINLIN LI, JIAN KANG, FENGKAI YAN, PENGJU DU, DIERK RAABE, AND GUODONG WANGAuthors Info & Affiliations

▲ 链接：

https://www.science.org/doi/10.1126/science.add7857

▲ 摘要：

从交通运输到轻量化设计再到安全的基础设施，很多领域都需要机械强度和延展性的承重材料。但其中一大挑战是在一种材料中统一这两种功能。

作者研究表明，在均匀伸长率&>20%的情况下，普通中锰钢可以加工成抗拉强度&>2.2吉帕。这需要多个横向锻造、深冷处理和回火步骤的结合。由层状和双重拓扑排列的马氏体与精细分散的保留奥氏体组成的分层微结构，同时激活多种微观机制来增强和延展性材料。

组织良好的马氏体中的位错滑移和渐进变形刺激相变协同作用产生了较高的延性。研究者表示，该纳米结构设计策略可以生产出强度为2吉帕且具有延展性的钢，具有大规模工业生产的潜力。

▲ Abstract：

Mechanically strong and ductile load–carrying materials are needed in all sectors, from transportation to lightweight design to safe infrastructure. Yet, a grand challenge is to unify both features in one material. We show that a plain medium-manganese steel can be processed to have a tensile strength &>2.2 gigapascals at a uniform elongation &>20%. This requires a combination of multiple transversal forging, cryogenic treatment, and tempering steps. A hierarchical microstructure that consists of laminated and twofold topologically aligned martensite with finely dispersed retained austenite simultaneously activates multiple micromechanisms to strengthen and ductilize the material. The dislocation slip in the well-organized martensite and the gradual deformation-stimulated phase transformation synergistically produce the high ductility. Our nanostructure design strategy produces 2 gigapascal–strength and yet ductile steels that have attractive composition and the potential to be produced at large industrial scales.

▲ 作者：CHUNQING MA, FELIX T. EICKEMEYER, SUN-HO LEE, DONG-HO KANG, SEOK JOON KWON, MICHAEL GRÄTZEL , AND NAM-GYU PARK

▲ 链接：

https://www.science.org/doi/10.1126/science.adf3349

▲ 摘要：

有大量研究和策略致力于提高钙钛矿薄膜的稳定性；然而，不同钙钛矿晶面在稳定性中的作用仍然未知。作者揭示了甲胺碘化铅（FAPbI₃）薄膜的面依赖性降解的潜在机制。研究明，（100）面基本上比（111）面更容易受到水分诱导的降解。

通过实验和理论研究相结合，研究揭示了降解机理；随着铅-碘键长距离的延长，观察到强烈的水黏附，这导致（100）面上的δ相变。通过工程设计，可以获得更高的（111）面表面分数，（111）为主的晶体FAPbI₃薄膜表现出优异的抗潮气稳定性。该发现阐明了未知的面相关降解机制和动力学。

▲ Abstract：

A myriad of studies and strategies have already been devoted to improving the stability of perovskite films; however, the role of the different perovskite crystal facets in stability is still unknown. Here, we reveal the underlying mechanisms of facet-dependent degradation of formamidinium lead iodide (FAPbI₃) films. We show that the (100) facet is substantially more vulnerable to moisture-induced degradation than the (111) facet. With combined experimental and theoretical studies, the degradation mechanisms are revealed; a strong water adhesion following an elongated lead-iodine (Pb-I) bond distance is observed, which leads to a δ-phase transition on the (100) facet. Through engineering, a higher surface fraction of the (111) facet can be achieved, and the (111)-dominated crystalline FAPbI₃ films show exceptional stability against moisture. Our findings elucidate unknown facet-dependent degradation mechanisms and kinetics.

▲ 作者：VIPIN S. RANA, CHRYSOULA KITSOU, SHRABONI DUTTA, MICHAEL H. RONZETTI, MIN ZHANG, QUENTIN BERNARD, ALEXIS A. SMITH, JULEN TOMáS-CORTáZAR, XIULI YANG, UTPAL PAL, etc.

▲ 链接：

https://www.science.org/doi/10.1126/science.abl3837

▲ 摘要：

蜱起源于近2.25亿年前的一种自由生活的食腐螨，已经进化成一种具有高度适应性的单系吸血体外寄生虫。与大多数喜欢单一脊椎动物宿主的地理活动受限的蜱种不同，硬蜱可以寄生在许多脊椎动物体内，传播不同的病原体。

硬蜱在其多年的生命周期中只经历三次进食活动，摄取的血餐几乎是它们体重的100倍。它们特有的生理适应可能是由其复杂的吸血和与共同进化的脊椎动物宿主的联系所形成的。蜱虫如何维持其复杂的胚胎后发育程序以及它们的媒介能力的分子基础尚不清楚。

作者发现，蜱含有一种功能性的JAK-STAT信号级联，可诱导强有力的抗菌反应，能够限制蜱传病原体的增殖。该途径在许多节肢动物中被 UPD等细胞因子样分子激活。但硬蜱基因组异常缺乏可识别的UPD直系同源物。

▲ Abstract：

Ticks have evolved into a monophyletic group of highly adapted blood-feeding ectoparasites that originated from a clade of free-living scavenger mites nearly 225 million years ago. Unlike most geographically confined tick species that prefer a single vertebrate host, Ixodes spp. can parasitize many vertebrates and transmit diverse pathogens. Ixodid ticks undergo only three feeding events during their multiyear lifespan, ingesting blood meals that are nearly 100 times their weight. Their characteristic physiological adaptations were likely shaped by their sophisticated hematophagy and associations with coevolving vertebrate hosts. The molecular basis of how ticks maintain their complex postembryonic developmental program as well as their vectorial competence remains unclear. Ticks contain a functional JAK–STAT signaling cascade that induces robust antibacterial responses capable of limiting the proliferation of tick-borne pathogens. The pathway is activated in many arthropods by cytokine-like molecules such as Unpaired (UPD). However, the Ixodes scapularis genome is unusually devoid of recognizable UPD orthologs.

▲ 作者：DONG-OH SEO, DAVID O’DONNELL, NIMANSHA JAIN, JASON D. ULRICH, JASMIN HERZ, YUHAO LI, MACKENZIE LEMIEUX, JIYE CHENG, HAO HU,, AND DAVID M. HOLTZMAN, etc.

▲ 链接：

https://www.science.org/doi/10.1126/science.add1236

▲ 摘要：

大脑中某些形式的Tau蛋白的积累与神经细胞的损失、炎症以及阿尔茨海默病和其他几种神经退行性疾病的认知能力下降有关。

载脂蛋白-E（APOE）是阿尔茨海默病最强的遗传风险因素，调节脑炎症和Tau介导的脑损伤；然而，肠道菌群也调节大脑炎症。

在Tau介导的脑损伤小鼠模型中，研究者发现，肠道微生物群的操纵导致炎症、Tau病理和脑损伤因性别和APOE依赖的方式大幅减少。

▲ Abstract：

The accumulation of certain forms of the tau protein in the brain is linked to loss of nerve cells, inflammation, and cognitive decline in Alzheimer’s disease and several other neurodegenerative diseases. Apolipoprotein-E (APOE), the strongest genetic risk factor for Alzheimer’s disease, regulates brain inflammation and tau-mediated brain damage; however, the gut microbiota also regulates brain inflammation. In a mouse model of tau-mediated brain injury, Seo et al. found that manipulation of the gut microbiota resulted in a strong reduction of inflammation, tau pathology, and brain damage in a sex- and APOE-dependent manner.

▲ 作者：TIANYI XIONG, CHANGWEI LI, XIULAN HE, BOYANG XIE, JIANWEI ZONG, YANAN JIANG, WENJIE MA, FEI WU, JUNJIE FEI, AND LANQUN MAO

▲ 链接：

https://www.science.org/doi/10.1126/science.adc9150

▲ 摘要：

利用人工流体系统再现基于离子通道的神经功能一直是神经形态计算和生物医学应用的一个理想目标。在这项研究中，聚电解质-受限流体忆阻器（PFM）成功地实现了神经形态功能，其中受限的聚电解质-离子相互作用导致了滞后的离子传输，从而导致了离子记忆效应。

采用超低能耗的PFM模拟了各种不同的电脉冲模式。PFM的流体特性使模拟化学调节电脉冲成为可能。更重要的是，化学-电信号转导是由单个PFM实现的。由于其结构与离子通道相似，PFM是通用的，易于与生物系统接口，为通过引入丰富的化学设计构建具有高级功能的神经形态设备铺平了道路。

▲ Abstract：

Reproducing ion channel–based neural functions with artificial fluidic systems has long been an aspirational goal for both neuromorphic computing and biomedical applications. In this study, neuromorphic functions were successfully accomplished with a polyelectrolyte-confined fluidic memristor (PFM), in which confined polyelectrolyte–ion interactions contributed to hysteretic ion transport, resulting in ion memory effects. Various electric pulse patterns were emulated by PFM with ultralow energy consumption. The fluidic property of PFM enabled the mimicking of chemical-regulated electric pulses. More importantly, chemical-electric signal transduction was implemented with a single PFM. With its structural similarity to ion channels, PFM is versatile and easily interfaces with biological systems, paving a way to building neuromorphic devices with advanced functions by introducing rich chemical designs.

▲ 作者：P. ROBIN, T. EMMERICH, A. ISMAIL, A. NIGUèS, Y. YOU, G.-H. NAM, A. KEERTHI, A. SIRIA, A. K. GEIM, AND L. BOCQUET

▲ 链接：

https://www.science.org/doi/10.1126/science.adc9931

▲ 摘要：

通过纳米级孔隙进行微调的离子传输是许多生物过程的关键，包括神经传递。最近的进展使水和离子的限制成为二维，揭示了在更大尺度上无法实现的传输特性，并引发了重现生物系统离子机械的希望。

作者通过实验证明了记忆出现在水电解质运输（亚）纳米级通道。他们揭示了两种类型的纳米流体忆阻器，取决于通道材料和限制，记忆范围从分钟到小时。研究解释了离子自组装或表面吸附等界面过程如何出现大的时间尺度，能够用纳米流控系统实现Hebbian学习。该结果为水电解芯片的仿生计算奠定了基础。

▲ Abstract：

Fine-tuned ion transport across nanoscale pores is key to many biological processes, including neurotransmission. Recent advances have enabled the confinement of water and ions to two dimensions, unveiling transport properties inaccessible at larger scales and triggering hopes of reproducing the ionic machinery of biological systems. Here we report experiments demonstrating the emergence of memory in the transport of aqueous electrolytes across (sub)nanoscale channels. We unveil two types of nanofluidic memristors depending on channel material and confinement, with memory ranging from minutes to hours. We explain how large time scales could emerge from interfacial processes such as ionic self-assembly or surface adsorption. Such behavior allowed us to implement Hebbian learning with nanofluidic systems. This result lays the foundation for biomimetic computations on aqueous electrolytic chips.