编译|未玖Science,31 JAN 2025, VOL 387, ISSUE 6733《迷信》2025年1月31日，第387卷，6733期资料迷信Materials ScienceTransforming achiral semiconductors into chiral domains with exceptional circular dichroism将非手性半导体转化为存在特别圆二色性的手性域▲ 作者：THOMAS J. UGRAS, RIVER B. CARSON, REILLY P. LYNCH, HAOYANG LI, YUAN YAO, LORENZO CUPELLINI, ET AL.▲链接：https://www.science.org/doi/10.1126/science.ado7201▲择要：硫化镉、硒化镉跟碲化镉的错误称半导体幻数尺寸簇（MSCs）的高浓度溶液被领导经由过程受控枯燥弯月面，从而构成手性MSC组件。这一进程使其跃迁偶极矩对齐，并发生了存在极强圆二色性的手性光学薄膜。滴铸膜的G因子高达1.30数目级，图案化膜的G因子高达1.06数目级，濒临实践极限。经由过程把持蒸发多少何外形，研讨组实现了差别外形跟尺寸的域，此中超越6平方毫米的同手性域可在左旋跟右旋手性之间腻滑过渡。该研讨成果提醒了弯月面堆积进程、超分子细丝及其MSC身分陈列之间的基础关联，以及其与新兴手性的关系。▲ Abstract：Highly concentrated solutions of asymmetric semiconductor magic-sized clusters (MSCs) of cadmium sulfide, cadmium selenide, and cadmium telluride were directed through a controlled drying meniscus front, resulting in the formation of chiral MSC assemblies. This process aligned their transition dipole moments and produced chiroptic films with exceptionally strong circular dichroism. G-factors reached magnitudes as high as 1.30 for drop-cast films and 1.06 for patterned films, approaching theoretical limits. By controlling the evaporation geometry, various domain shapes and sizes were achieved, with homochiral domains exceeding 6 square millimeters that transition smoothly between left- and right-handed chirality. Our results uncovered fundamental relationships between meniscus deposition processes, the alignment of supramolecular filaments and their MSC constituents, and their connection to emergent chiral properties.Nondeterministic dynamics in the η-to-θ phase transition of alumina nanoparticles氧化铝纳米颗粒η-θ相变的非断定性能源学▲ 作者：MASAYA SAKAKIBARA, MINORU HANAYA, TAKAYUKI NAKAMURO AND EIICHI NAKAMURA▲链接：https://www.science.org/doi/10.1126/science.adr8891▲择要：相图跟晶体学是研讨构造相变的尺度东西，而在原子程度上获取能源学信息被以为必弗成少，但颇具挑衅性。氧化铝的η-θ相变在块体中是单向的，并坚持了晶格取向。研讨组报道了一个统计能源学研讨的常见例子，标明对块体Al(OH)3名义上的纳米颗粒，这种相变经由过程遍历均衡态经熔融态非断定性地产生，而且晶格取向的影象在此进程中丧失。成果发明，彼此转化率对电子剂量率不敏感，且该进程的吉布斯活化自在能较小。这些非断定性能源学应当是在块状晶体高名义能地区产生晶体成核的一个要害特点。▲ Abstract：Phase diagrams and crystallography are standard tools for studying structural phase transitions, whereas acquiring kinetic information at the atomistic level has been considered essential but challenging. The η-to-θ phase transition of alumina is unidirectional in bulk and retains the crystal lattice orientation. We report a rare example of a statistical kinetics study showing that for nanoparticles on a bulk Al(OH)3 surface, this phase transition occurs nondeterministically through an ergodic equilibrium through the molten state, and the memory of the lattice orientation is lost in this process. The rate of the interconversion was found to be insensitive to the electron dose rate, and this process had a small Gibbs free energy of activation. These nondeterministic kinetics should be a key feature of crystal nucleation occurring in high-surface-energy regions of bulk crystals.化学ChemistryConformational dynamics of a multienzyme complex in anaerobic carbon fixation厌氧固碳中多酶复合物的构象能源学▲ 作者：MAX DONGSHENG YIN, OLIVIER N. LEMAIRE, JOSé GUADALUPE ROSAS JIMéNEZ, MéLISSA BELHAMRI, ANNA SHEVCHENKO, GERHARD HUMMER, ET AL.▲链接：https://www.science.org/doi/10.1126/science.adr9672▲择要：在陈旧的微生物Wood-Ljungdahl道路中，二氧化碳（CO2）以多步调进程牢固，终极在双功效一氧化碳脱氢酶/乙酰辅酶A分解酶复合物（CODH/ACS）上分解乙酰辅酶A （acetyl-CoA）。研讨组展现了气体转化产乙酸菌乙醇梭菌卵白CODH/ACS的构造快照，表征了全部反映的分子编排，包含电子转移到CODH停止CO2复原、从类咕啉铁硫卵白（CoFeSP）朋友到ACS活性位点的甲基转移，以及乙酰辅酶A的发生。与CODH差别，多构造域ACS阅历了宏大的构象变更，构成了与CODH活性位点的外部衔接，包容CoFeSP停止甲基转移，并维护反映旁边体。总而言之，这些构造使人们可能绘制出这种酶的具体反映机制，这对厌氧生物中CO2的牢固至关主要。▲ Abstract：In the ancient microbial Wood-Ljungdahl pathway, carbon dioxide (CO2) is fixed in a multistep process that ends with acetyl–coenzyme A (acetyl-CoA) synthesis at the bifunctional carbon monoxide dehydrogenase/acetyl-CoA synthase complex (CODH/ACS). In this work, we present structural snapshots of the CODH/ACS from the gas-converting acetogen Clostridium autoethanogenum, characterizing the molecular choreography of the overall reaction, including electron transfer to the CODH for CO2 reduction, methyl transfer from the corrinoid iron-sulfur protein (CoFeSP) partner to the ACS active site, and acetyl-CoA production. Unlike CODH, the multidomain ACS undergoes large conformational changes to form an internal connection to the CODH active site, accommodate the CoFeSP for methyl transfer, and protect the reaction intermediates. Altogether, the structures allow us to draw a detailed reaction mechanism of this enzyme, which is crucial for CO2 fixation in anaerobic organisms.大众卫生Public HealthPre-exposure antibody prophylaxis protects macaques from severe influenza裸露前抗体防备性维护猕猴免受重大流感▲ 作者：MASARU KANEKIYO, REBECCA A. GILLESPIE, KRISTINE COOPER, VANESSA GUERRA CANEDO, PRISCILA M. S. CASTANHA, AMARENDRA PEGU, ET AL.▲链接：https://www.science.org/doi/10.1126/science.ado6481▲择要：流感病毒年夜风行跟节令性风行病夺去了有数人的性命。存在年夜风行潜力的流感病毒重复产生人畜共患外溢，亟需采用无效对策。在这项任务中，研讨组发明普遍中跟抗体（bnAb） MEDI8852裸露前防备在维护食蟹猴免受高致病性禽流感H5N1气溶胶病毒沾染惹起的重症疾病方面十分无效。在实验剂量下，维护感化是抗体剂量依附性的，但自力于Fc介导的效应器功效。接收每公斤体重10毫克或更高剂量MEDI8852的猕猴在沾染后的呼吸功效侵害能够疏忽不计，而对比植物却未能免于重症疾病跟逝世亡。鉴于MEDI8852跟其余bnAb的普遍性，研讨组期望，弗成预感的年夜风行性甲型流感病毒是可防备的。▲ Abstract：Influenza virus pandemics and seasonal epidemics have claimed countless lives. Recurrent zoonotic spillovers of influenza viruses with pandemic potential underscore the need for effective countermeasures. In this study, we show that pre-exposure prophylaxis with broadly neutralizing antibody (bnAb) MEDI8852 is highly effective in protecting cynomolgus macaques from severe disease caused by aerosolized highly pathogenic avian influenza H5N1 virus infection. Protection was antibody dose–dependent yet independent of Fc-mediated effector functions at the dose tested. Macaques receiving MEDI8852 at 10 milligrams per kilogram or higher had negligible impairment of respiratory function after infection, whereas control animals were not protected from severe disease and fatality. Given the breadth of MEDI8852 and other bnAbs, we anticipate that protection from unforeseen pandemic influenza A viruses is achievable.植物学ZoologyTiger recovery amid people and poverty山君种群在群体跟贫苦中苏醒▲ 作者：YADVENDRADEV V. JHALA, NINAD AVINASH MUNGI, RAJESH GOPAL AND QAMAR QURESHI▲链接：https://www.science.org/doi/10.1126/science.adk4827▲择要：规复年夜型但存在主要生态意思的食肉植物是一项艰难的寰球挑衅。印度是天下上生齿最多的地域，山君（孟加拉虎）的种群规复为评价巨型植物规复的社会生态驱动要素供给了一个奇特机遇。在从前的二十年里，山君的栖身地增添了30%（每年2929平方千米），招致寰球最年夜的山君种群占地约138200平方千米。山君始终盘踞着不人类、猎物丰盛的维护区（35255平方千米），但也在与约6000万人共享的附近连通栖身地假寓。山君的消散跟灭尽以武装抵触、贫苦跟普遍的地皮应用变更为特点。只有社会经济繁华跟政治稳固盘踞优势，为山君预留生活空间就能够实现地皮共享。印度虎群的规复让人们对巨型植物的规复持谨慎悲观立场，尤其是在南半球。▲ Abstract：Recovery of large yet ecologically important carnivores poses a formidable global challenge. Tiger (Panthera tigris) recovery in India, the world’s most populated region, offers a distinct opportunity to evaluate the socio-ecological drivers of megafauna recovery. Tiger occupancy increased by 30% (at 2929 square kilometers per year) over the past two decades, leading to the largest global population occupying ~138,200 square kilometers. Tigers persistently occupied human-free, prey-rich protected areas (35,255 square kilometers) but also colonized proximal connected habitats that were shared with ~60 million people. Tiger absence and extinction were characterized by armed conflict, poverty, and extensive land-use changes. Sparing land for tigers enabled land sharing, provided that socioeconomic prosperity and political stability prevailed. India’s tiger recovery offers cautious optimism for megafauna recovery, particularly in the Global South.Ancient genomics and the origin, dispersal, and development of domestic sheep古基因组学提醒野生绵羊的来源、传布跟开展▲ 作者：KEVIN G. DALY, VICTORIA E. MULLIN, ANDREW J. HARE, áINE HALPIN, VALERIA MATTIANGELI, MATTHEW D. TEASDALE, ET AL.▲链接：https://www.science.org/doi/10.1126/science.adn2094▲择要：野生绵羊（Ovis aries）的来源跟史前演变尚未完整明白；为懂得决这个成绩，研讨组从欧亚年夜陆采样的逾越12000年的118个古基因组中天生了数据。公元前8000年阁下，来自土耳此中部地域的基因组在遗传学上濒临绵羊的驯化来源，但不克不及完整说明厥后种群的先人，这标明了野生先人的镶嵌融会。基因组特点标明，现代牧平易近对绵羊的毛色形式、有角性跟成长速率停止了抉择。只管首批欧洲绵羊群来源于土耳其（与现代人类基因组的发明有明显类似之处），但研讨组在青铜时期发明了大批与西部草原相干的绵羊先人。▲ Abstract：The origins and prehistory of domestic sheep (Ovis aries) are incompletely understood; to address this, we generated data from 118 ancient genomes spanning 12,000 years sampled from across Eurasia. Genomes from Central Türkiye ~8000 BCE are genetically proximal to the domestic origins of sheep but do not fully explain the ancestry of later populations, suggesting a mosaic of wild ancestries. Genomic signatures indicate selection by ancient herders for pigmentation patterns, hornedness, and growth rate. Although the first European sheep flocks derive from Türkiye, in a notable parallel with ancient human genome discoveries, we detected a major influx of Western steppe–related ancestry in the Bronze Age.[db:摘要]
