編譯 | 馮維維
SCIENCE, January 2023, Volume 379 Issue 6628
《科學(xué)》2023年1月，第379卷，6628期
物理學(xué)Physics
Ductile 2-GPa steels with hierarchical substructure
具有分層子結(jié)構(gòu)的2吉帕韌性鋼
▲ 作者：YUNJIE LI, GUO YUAN, LINLIN LI, JIAN KANG, FENGKAI YAN, PENGJU DU, DIERK RAABE, AND GUODONG WANGAuthors Info & Affiliations
▲ 鏈接：
https://www.science.org/doi/10.1126/science.add7857
▲ 摘要：
從交通運(yùn)輸?shù)捷p量化設(shè)計(jì)再到安全的基礎(chǔ)設(shè)施，很多領(lǐng)域都需要機(jī)械強(qiáng)度和延展性的承重材料。但其中一大挑戰(zhàn)是在一種材料中統(tǒng)一這兩種功能。
作者研究表明，在均勻伸長(zhǎng)率>20%的情況下，普通中錳鋼可以加工成抗拉強(qiáng)度>2.2吉帕。這需要多個(gè)橫向鍛造、深冷處理和回火步驟的結(jié)合。由層狀和雙重拓?fù)渑帕械鸟R氏體與精細(xì)分散的保留奧氏體組成的分層微結(jié)構(gòu)，同時(shí)激活多種微觀機(jī)制來增強(qiáng)和延展性材料。
組織良好的馬氏體中的位錯(cuò)滑移和漸進(jìn)變形刺激相變協(xié)同作用產(chǎn)生了較高的延性。研究者表示，該納米結(jié)構(gòu)設(shè)計(jì)策略可以生產(chǎn)出強(qiáng)度為2吉帕且具有延展性的鋼，具有大規(guī)模工業(yè)生產(chǎn)的潛力。
▲ 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.
Unveiling facet-dependent degradation and facet engineering for stable perovskite solar cells
穩(wěn)定鈣鈦礦太陽(yáng)能電池的面依賴性降解和面工程
▲ 作者：CHUNQING MA, FELIX T. EICKEMEYER, SUN-HO LEE, DONG-HO KANG, SEOK JOON KWON, MICHAEL GR?TZEL , AND NAM-GYU PARK
▲ 鏈接：
https://www.science.org/doi/10.1126/science.adf3349
▲ 摘要：
有大量研究和策略致力于提高鈣鈦礦薄膜的穩(wěn)定性；然而，不同鈣鈦礦晶面在穩(wěn)定性中的作用仍然未知。作者揭示了甲胺碘化鉛（FAPbI3）薄膜的面依賴性降解的潛在機(jī)制。研究明，（100）面基本上比（111）面更容易受到水分誘導(dǎo)的降解。
通過實(shí)驗(yàn)和理論研究相結(jié)合，研究揭示了降解機(jī)理；隨著鉛-碘鍵長(zhǎng)距離的延長(zhǎng)，觀察到強(qiáng)烈的水黏附，這導(dǎo)致（100）面上的δ相變。通過工程設(shè)計(jì)，可以獲得更高的（111）面表面分?jǐn)?shù)，（111）為主的晶體FAPbI3薄膜表現(xiàn)出優(yōu)異的抗潮氣穩(wěn)定性。該發(fā)現(xiàn)闡明了未知的面相關(guān)降解機(jī)制和動(dòng)力學(xué)。
▲ 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.
微生物學(xué)Microbiology
Dome1–JAK–STAT signaling between parasite and host integrates vector immunity and development
寄生蟲和宿主間信號(hào)傳遞整合媒介免疫和發(fā)育
▲ 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.
▲ 鏈接：
https://www.science.org/doi/10.1126/science.abl3837
▲ 摘要：
蜱起源于近2.25億年前的一種自由生活的食腐螨，已經(jīng)進(jìn)化成一種具有高度適應(yīng)性的單系吸血體外寄生蟲。與大多數(shù)喜歡單一脊椎動(dòng)物宿主的地理活動(dòng)受限的蜱種不同，硬蜱可以寄生在許多脊椎動(dòng)物體內(nèi)，傳播不同的病原體。
硬蜱在其多年的生命周期中只經(jīng)歷三次進(jìn)食活動(dòng)，攝取的血餐幾乎是它們體重的100倍。它們特有的生理適應(yīng)可能是由其復(fù)雜的吸血和與共同進(jìn)化的脊椎動(dòng)物宿主的聯(lián)系所形成的。蜱蟲如何維持其復(fù)雜的胚胎后發(fā)育程序以及它們的媒介能力的分子基礎(chǔ)尚不清楚。
作者發(fā)現(xiàn)，蜱含有一種功能性的JAK-STAT信號(hào)級(jí)聯(lián)，可誘導(dǎo)強(qiáng)有力的抗菌反應(yīng)，能夠限制蜱傳病原體的增殖。該途徑在許多節(jié)肢動(dòng)物中被 UPD等細(xì)胞因子樣分子激活。但硬蜱基因組異常缺乏可識(shí)別的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.
ApoE isoform– and microbiota-dependent progression of neurodegeneration in a mouse model of tauopathy
Tau小鼠病理模型解析依賴ApoE亞型和微生物群的神經(jīng)退行性疾病
▲ 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.
▲ 鏈接：
https://www.science.org/doi/10.1126/science.add1236
▲ 摘要：
大腦中某些形式的Tau蛋白的積累與神經(jīng)細(xì)胞的損失、炎癥以及阿爾茨海默病和其他幾種神經(jīng)退行性疾病的認(rèn)知能力下降有關(guān)。
載脂蛋白-E（APOE）是阿爾茨海默病最強(qiáng)的遺傳風(fēng)險(xiǎn)因素，調(diào)節(jié)腦炎癥和Tau介導(dǎo)的腦損傷；然而，腸道菌群也調(diào)節(jié)大腦炎癥。
在Tau介導(dǎo)的腦損傷小鼠模型中，研究者發(fā)現(xiàn)，腸道微生物群的操縱導(dǎo)致炎癥、Tau病理和腦損傷因性別和APOE依賴的方式大幅減少。
▲ 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.
生物物理學(xué)Biophysics
Neuromorphic functions with a polyelectrolyte-confined fluidic memristor
聚電解質(zhì)受限流體憶阻器的神經(jīng)形態(tài)功能
▲ 作者：TIANYI XIONG, CHANGWEI LI, XIULAN HE, BOYANG XIE, JIANWEI ZONG, YANAN JIANG, WENJIE MA, FEI WU, JUNJIE FEI, AND LANQUN MAO
▲ 鏈接：
https://www.science.org/doi/10.1126/science.adc9150
▲ 摘要：
利用人工流體系統(tǒng)再現(xiàn)基于離子通道的神經(jīng)功能一直是神經(jīng)形態(tài)計(jì)算和生物醫(yī)學(xué)應(yīng)用的一個(gè)理想目標(biāo)。在這項(xiàng)研究中，聚電解質(zhì)-受限流體憶阻器（PFM）成功地實(shí)現(xiàn)了神經(jīng)形態(tài)功能，其中受限的聚電解質(zhì)-離子相互作用導(dǎo)致了滯后的離子傳輸，從而導(dǎo)致了離子記憶效應(yīng)。
采用超低能耗的PFM模擬了各種不同的電脈沖模式。PFM的流體特性使模擬化學(xué)調(diào)節(jié)電脈沖成為可能。更重要的是，化學(xué)-電信號(hào)轉(zhuǎn)導(dǎo)是由單個(gè)PFM實(shí)現(xiàn)的。由于其結(jié)構(gòu)與離子通道相似，PFM是通用的，易于與生物系統(tǒng)接口，為通過引入豐富的化學(xué)設(shè)計(jì)構(gòu)建具有高級(jí)功能的神經(jīng)形態(tài)設(shè)備鋪平了道路。
▲ 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.
Long-term memory and synapse-like dynamics in two-dimensional nanofluidic channels
二維納米流體通道中的長(zhǎng)時(shí)記憶和突觸樣動(dòng)力學(xué)
▲ 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
▲ 鏈接：
https://www.science.org/doi/10.1126/science.adc9931
▲ 摘要：
通過納米級(jí)孔隙進(jìn)行微調(diào)的離子傳輸是許多生物過程的關(guān)鍵，包括神經(jīng)傳遞。最近的進(jìn)展使水和離子的限制成為二維，揭示了在更大尺度上無(wú)法實(shí)現(xiàn)的傳輸特性，并引發(fā)了重現(xiàn)生物系統(tǒng)離子機(jī)械的希望。
作者通過實(shí)驗(yàn)證明了記憶出現(xiàn)在水電解質(zhì)運(yùn)輸（亞）納米級(jí)通道。他們揭示了兩種類型的納米流體憶阻器，取決于通道材料和限制，記憶范圍從分鐘到小時(shí)。研究解釋了離子自組裝或表面吸附等界面過程如何出現(xiàn)大的時(shí)間尺度，能夠用納米流控系統(tǒng)實(shí)現(xiàn)Hebbian學(xué)習(xí)。該結(jié)果為水電解芯片的仿生計(jì)算奠定了基礎(chǔ)。
▲ 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.
