Nature, Volume 637 Issue 8045, 9 January 2025《天然》第637卷，8045期，2025年1月9日物理学PhysicsParticle exchange statistics beyond fermions and bosons超出费米子跟玻色子的粒子交流统计▲ 作者：Zhiyuan Wang Kaden R. A. Hazzard▲ 链接：https://www.nature.com/articles/s41586-024-08262-7▲择要：人们广泛以为，在量子力学中，除了二维的恣意子，只有费米子跟玻色子两种粒子交流统计。准则上，第二种破例被称为非统计。它延长到二维之外，被以为在物理上同等于费米子跟玻色子。研讨者证实了物理体系中能够存在与费米子或玻色子等价的非平常准统计量。这些新范例的雷同粒子遵守狭义不相容道理，招致与任何自在费米子跟玻色子体系差别的奇怪自在粒子热力学。他们经由过程开展粒子的第二次量子化来表述其实践。该实践天然地包含准确可解的非彼此感化实践，并联合了诸如部分性等物理束缚。而后，他们在一维跟二维中构建了一组准确可解的量子自旋模子，此中自在粒子以准粒子的情势呈现，其交流统计量能够被物理察看到，且与费米子跟玻色子显明差别。这证实了在凝集态体系中存在一种新型准粒子的可能性，更有可能是从前未斟酌过的基础粒子范例。▲ Abstract：It is commonly believed that there are only two types of particle exchange statistics in quantum mechanics, fermions and bosons, with the exception of anyons in two dimensions. In principle, a second exception known as parastatistics, which extends outside two dimensions, has been considered but was believed to be physically equivalent to fermions and bosons. Here we show that non-trivial parastatistics inequivalent to either fermions or bosons can exist in physical systems. These new types of identical particle obey generalized exclusion principles, leading to exotic free-particle thermodynamics distinct from any system of free fermions and bosons. We formulate our theory by developing a second quantization of paraparticles that naturally includes exactly solvable non-interacting theories and incorporates physical constraints such as locality. We then construct a family of exactly solvable quantum spin models in one and two dimensions, in which free paraparticles emerge as quasiparticle excitations, and their exchange statistics can be physically observed and are notably distinct from fermions and bosons. This demonstrates the possibility of a new type of quasiparticle in condensed matter systems and—more speculatively—the potential for previously unconsidered types of elementary particle.Excitons in the fractional quantum Hall effect分数目子霍尔效应中的激子▲ 作者：Naiyuan J. Zhang, Ron Q. Nguyen, Navketan Batra, Xiaoxue Liu, Kenji Watanabe, Takashi Taniguchi, D. E. Feldman J. I. A. Li▲ 链接：https://www.nature.com/articles/s41586-024-08274-3▲择要：激子，即电子跟空穴的库仑驱动约束态，平日由整数电荷构成。但是，在受电荷分数化影响的双层体系中，能够呈现一种更风趣的层间激子情势，此中在携带分数电荷的组分之间产生配对。只管对这些分数激子有很多实践猜测，但它们的试验察看仍未被摸索。研讨者报道了分数目子霍尔效应态中激子对的输运特点。经由过程探测这些激子的构成及其对潜伏波函数的影响，他们发明了两种新的物资量子相。此中一个能够被看作是总添补为1的激子凝集的分数对应物；而另一个则波及一种更不平常的激子范例，它遵守非玻色子量子统计，挑衅玻色子激子的尺度模子。▲ Abstract：Excitons, Coulomb-driven bound states of electrons and holes, are typically composed of integer charges. However, in bilayer systems influenced by charge fractionalization, a more interesting form of interlayer exciton can emerge, in which pairing occurs between constituents that carry fractional charges. Despite numerous theoretical predictions for these fractional excitons, their experimental observation has remained unexplored. Here we report transport signatures of excitonic pairing in fractional quantum Hall effect states. By probing the composition of these excitons and their impact on the underlying wavefunction, we discover two new types of quantum phases of matter. One of these can be viewed as the fractional counterpart of the exciton condensate at a total filling of 1, whereas the other involves a more unusual type of exciton that obeys non-bosonic quantum statistics, challenging the standard model of bosonic excitons.化学ChemistryEmergence of a distinct mechanism of C–N bond formation in photoenzymes光酶中C-N键构成的奇特机制的呈现▲ 作者：Felix C. Raps, Ariadna Rivas-Souchet, Chey M. Jones Todd K. Hyster▲ 链接：https://www.nature.com/articles/s41586-024-08138-w▲择要：因为氮杂环在小分子药物跟农用化学品中无处不在，C-N键的构成对古代化学分解是弗成或缺的。烯烃与未活化烯烃的氢胺化反映是构建这些键的原子经济战略。但是，当制备完整代替的碳破体核心时，这些反映很难浮现错误称。研讨者报道了一种应用Baeyer-Villiger单加氧酶制备2,2-二代替吡咯烷的光酶烯烃氢胺化反映。5轮卵白质工程取得了一个渐变体，供给了精良的产品收率跟破体抉择性。与依附于胺或烯烃氧化构成C-N键的相干光化学氢胺反映差别，这项研讨应用了复原天生的苯基跟氮孤对的空间彼此感化。这种反键彼此感化下降了自在基的氧化电位，使电子转移到黄素辅因子。试验标明，酶微情况在实现翻新的C-N键构成机制中是必弗成少的，这在小分子催化中是不相似的。分子能源学模仿研讨了酶活性位点的底物，进一步支撑了这一假设。这项任务长短天然生物催化中新兴机制的一个常见例子。在这种机制中，酶能够取得其单个组分所不的机制。咱们的研讨展现了应用卵白质工程加强紧迫机制的潜力，为化学分解中未处理的挑衅供给奇特的机制处理计划。▲ Abstract：C–N bond formation is integral to modern chemical synthesis owing to the ubiquity of nitrogen heterocycles in small-molecule pharmaceuticals and agrochemicals. Alkene hydroamination with unactivated alkenes is an atom-economical strategy for constructing these bonds. However, these reactions are challenging to render asymmetric when preparing fully substituted carbon stereocentres. Here we report a photoenzymatic alkene hydroamination to prepare 2,2-disubstituted pyrrolidines by a Baeyer–Villiger mono-oxygenase. Five rounds of protein engineering afforded a mutant, providing excellent product yield and stereoselectivity. Unlike related photochemical hydroaminations, which rely on the oxidation of the amine or alkene for C–N bond formation, this work exploits a through-space interaction of a reductively generated benzylic radical and the nitrogen lone pair. This antibonding interaction lowers the oxidation potential of the radical, enabling electron transfer to the flavin cofactor. Experiments indicate that the enzyme microenvironment is essential in enabling a innovative C–N bond formation mechanism with no parallel in small-molecule catalysis. Molecular dynamics simulations were performed to investigate the substrate in the enzyme active site, which further support this hypothesis. This work is a rare example of an emerging mechanism in non-natural biocatalysis in which an enzyme has access to a mechanism that its individual components do not. Our study showcases the potential of enhancing emergent mechanisms using protein engineering to provide unique mechanistic solutions to unanswered challenges in chemical synthesis.Li2ZrF6-based electrolytes for durable lithium metal batteries用于耐用锂金属电池的Li2ZrF6基电解质▲ 作者：Qingshuai Xu, Tan Li, Zhijin Ju, Guangxu Chen, Daiqi Ye, Geoffrey I. N. Waterhouse, Yingying Lu, Xuejun Lai, Guangmin Zhou, Lin Guo, Keyou Yan, Xinyong Tao, Hong Li Yongcai Qiu▲ 链接：https://www.nature.com/articles/s41586-024-08294-z▲ 择要：锂（Li）金属电池（MNB）是一种很有前程的高能量密度可充电电池。但是，由高活性锂跟非水电解质之间的反映构成的锂枝晶招致了保险性成绩跟疾速的容量衰减。开辟牢靠的固体电解质界面临于实现高速度跟长命命的LMB至关主要，但在技巧上依然存在挑衅性。研讨者证实了在含有LiPF6的LMB碳酸盐电解质中增加适量的m-Li2ZrF6（单斜晶体的）纳米颗粒，有助于在施加电压的驱动下将大批的ZrF62 -离子开释到电解质中，转化为t-Li2ZrF6（三方晶系），并在原位构成稳固的固体-电解质界面，存在高锂离子电导率。盘算电镜跟高温透射电镜研讨标明，富m-Li2ZrF6固电解质界面的原位构成明显加强了锂离子的转移，克制了锂枝晶的成长。成果标明，采取LiFePO4阴极、三维锂碳阳极跟Li2ZrF6基电解质组装的lmb在3000次轮回后存在较高的容量坚持率（ 80.0%），年夜年夜进步了轮回稳固性。这一成绩代表了当先的机能，因而在现实的高速度前提下，为耐用的LMB供给了牢靠的基于Li2ZrF6的电解质。▲ Abstract：Lithium (Li) metal batteries (LMBs) are promising for high-energy-density rechargeable batteries. However, Li dendrites formed by the reaction between highly active Li and non-aqueous electrolytes lead to safety concerns and rapid capacity decay. Developing a reliable solid–electrolyte interphase is critical for realizing high-rate and long-life LMBs, but remains technically challenging. Here we demonstrate that adding excess m-Li2ZrF6 (monoclinic) nanoparticles to a commercial LiPF6-containing carbonate electrolyte of LMBs facilitates the release of abundant ZrF62– ions into the electrolyte driven by the applied voltage, converting to t-Li2ZrF6 (trigonal) and creating a stable solid–electrolyte interphase in situ with high Li-ion conductivity. Computational and cryogenic transmission electron microscopy studies revealed that the in situ formation of the t-Li2ZrF6-rich solid–electrolyte interphase markedly enhanced Li-ion transfer and suppressed the growth of Li dendrites. As a result, LMBs assembled with LiFePO4 cathodes (areal loading, 1.8/2.2 mAh cm-2), three-dimensional Li–carbon anodes (50- m-thick Li) and Li2ZrF6-based electrolyte displayed greatly improved cycling stability with high capacity retention ( 80.0%) after 3,000 cycles (1C/2C rate). This achievement represents leading performance and, thus, delivers a reliable Li2ZrF6-based electrolyte for durable LMBs under practical high-rate conditions.性命迷信Life ScienceLearning-associated astrocyte ensembles regulate memory recall进修相干星形胶质细胞群调理影象回想▲ 作者：Michael R. Williamson, Wookbong Kwon, Junsung Woo, Yeunjung Ko, Ehson Maleki, Kwanha Yu, Sanjana Murali, Debosmita Sardar Benjamin Deneen▲ 链接：https://www.nature.com/articles/s41586-024-08170-w▲择要：影象构成跟回想的物理表示是尚未处理的基础成绩。在细胞程度上，被称为影象印痕的神经元聚集被进修变乱激活，并把持影象回想。星形胶质细胞凑近神经元，参加一系列支撑神经通报跟回路可塑性的运动。别的，星形胶质细胞表示出教训依附的可塑性，只管星形胶质细胞的特定聚集能否参加影象回想尚不明白。研讨者发明进修变乱引诱海马星形胶质细胞子会合的c-Fos表白，并随后调理小鼠海马回路的功效。进修变乱后星形胶质细胞群与c-Fos的穿插标志标明它们与印迹神经元亲密相干，这些星形胶质细胞群的从新激活安慰影象回想。在分子程度上，进修相干星形胶质细胞（LAA）群表示出核因子I-A的表白降低，其在该群体中的抉择性删除克制了影象回想。综上所述，这一数据断定LAA聚集是一种可塑性的情势，足以激起影象回想，并标明星形胶质细胞是印迹的活泼身分。▲ Abstract：The physical manifestations of memory formation and recall are fundamental questions that remain unresolved1. At the cellular level, ensembles of neurons called engrams are activated by learning events and control memory recall. Astrocytes are found in close proximity to neurons and engage in a range of activities that support neurotransmission and circuit plasticity. Moreover, astrocytes exhibit experience-dependent plasticity, although whether specific ensembles of astrocytes participate in memory recall remains obscure. Here we show that learning events induce c-Fos expression in a subset of hippocampal astrocytes, and that this subsequently regulates the function of the hippocampal circuit in mice. Intersectional labelling of astrocyte ensembles with c-Fos after learning events shows that they are closely affiliated with engram neurons, and reactivation of these astrocyte ensembles stimulates memory recall. At the molecular level, learning-associated astrocyte (LAA) ensembles exhibit elevated expression of nuclear factor I-A, and its selective deletion from this population suppresses memory recall. Taken together, our data identify LAA ensembles as a form of plasticity that is sufficient to provoke memory recall and indicate that astrocytes are an active component of the engram.Foundation models for fast, label-free detection of glioma infiltration疾速、无标志检测胶质瘤浸润的基本模子▲ 作者：Akhil Kondepudi, Melike Pekmezci, Xinhai Hou, Katie Scotford, Cheng Jiang, Akshay Rao, Edward S. Harake, Asadur Chowdury, Wajd Al-Holou, Lin Wang, Aditya Pandey, Pedro R. Lowenstein, Maria G. Castro, Lisa Irina Koerner, Thomas Roetzer-Pejrimovsky, Georg Widhalm, Sandra Camelo-Piragua, Misha Movahed-Ezazi, Daniel A. Orringer, Honglak Lee, Christian Freudiger, Mitchel Berger, Shawn Hervey-Jumper Todd Hollon▲ 链接：https://www.nature.com/articles/s41586-024-08169-3▲ 择要：胶质瘤医治的一个要害挑衅是在手术中检测肿瘤浸润以实现保险的最年夜切除。可怜的是，年夜少数胶质瘤患者术后可保险切除剩余肿瘤，招致晚期复发跟生活率下降。研讨者提出了一种疾速（ 10 s）跟正确检测新颖，未经处置的手术构造中胶质瘤浸润的视觉基本模子——FastGlioma。该模子可在疾速、无标志的光学显微镜下应用年夜范围自我监视（约400万张图像）停止预练习，并停止微调以输出一个尺度化的评分。该评分标明肿瘤浸润水平在全片光学图像中。在一项前瞻性、多核心、国际洋溢性胶质瘤患者检测行列（n = 220）中，FastGlioma可能检测并量化肿瘤浸润水平，其在受试者任务特点曲线下的均匀面积为92.1±0.9%。在一项头部仇家部的前瞻性研讨中，该模子在手术时期检测肿瘤浸润方面的表示优于图像领导跟荧光领导帮助手腕（n = 129）。依据天下卫生构造的界说，该模子在差别的患者生齿统计、医疗核心跟洋溢性胶质瘤分子亚型中表示依然很高。该模子在其余成人跟儿童脑肿瘤诊断中表现出零概率通用性，标明这一基本模子有可能被用作领导脑肿瘤手术的通用帮助东西。这些发明代表了医学基本模子在开释人工智能在癌症患者照顾护士中的感化方面的变更潜力。▲ Abstract：A critical challenge in glioma treatment is detecting tumour infiltration during surgery to achieve safe maximal resection. Unfortunately, safely resectable residual tumour is found in the majority of patients with glioma after surgery, causing early recurrence and decreased survival. Here we present FastGlioma, a visual foundation model for fast ( 10 s) and accurate detection of glioma infiltration in fresh, unprocessed surgical tissue. FastGlioma was pretrained using large-scale self-supervision (around 4 million images) on rapid, label-free optical microscopy, and fine-tuned to output a normalized score that indicates the degree of tumour infiltration within whole-slide optical images. In a prospective, multicentre, international testing cohort of patients with diffuse glioma (n = 220), FastGlioma was able to detect and quantify the degree of tumour infiltration with an average area under the receiver operating characteristic curve of 92.1 ± 0.9%. FastGlioma outperformed image-guided and fluorescence-guided adjuncts for detecting tumour infiltration during surgery by a wide margin in a head-to-head, prospective study (n = 129). The performance of FastGlioma remained high across diverse patient demographics, medical centres and diffuse glioma molecular subtypes as defined by the World Health Organization. FastGlioma shows zero-shot generalization to other adult and paediatric brain tumour diagnoses, demonstrating the potential for our foundation model to be used as a general-purpose adjunct for guiding brain tumour surgeries. These findings represent the transformative potential of medical foundation models to unlock the role of artificial intelligence in the care of patients with cancer.小编：[db:摘要]
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