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《科学》(20230728出版)一周论文导读

 

Science, 28 JUL 2023, Volume 381 Issue 6656

《科学》2023年7月28日,第381卷,6656期

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物理学Physics

Observation of universal Hall response in strongly interacting Fermions

强相互作用费米子中普遍霍尔响应的观测

作者:T.-W. ZHOU, G. CAPPELLINI et al.

链接:

https://www.science.org/doi/full/10.1126/science.add1969

摘要:

在这项研究中,我们使用了一个原子量子模拟器去追踪超冷费米子在人工磁场缠绕双线中的运动。通过可控淬火动力学,我们测量了一系列合成隧穿和原子相互作用强度的霍尔响应。

我们揭示了一个交互阈值之上的普遍的交互独立行为,这与理论分析相一致。可以达到难以计算状态证明了量子模拟在描述物质强相关拓扑状态方面的能力。

Abstract:

HIn this work, we used an atomic quantum simulator in which we tracked the motion of ultracold fermions in two-leg ribbons threaded by artificial magnetic fields. Through controllable quench dynamics, we measured the Hall response for a range of synthetic tunneling and atomic interaction strengths. We unveil a universal interaction-independent behavior above an interaction threshold, in agreement with theoretical analyses. The ability to reach hard-to-compute regimes demonstrates the power of quantum simulation to describe strongly correlated topological states of matter.

Tensile cracks can shatter classical speed limits

拉伸裂纹可以打破传统的速度限制

作者:MENG WANG, SONGLIN SHI et al.

链接:

https://www.science.org/doi/full/10.1126/science.adg7693

摘要:

脆性材料会因为快速开裂而失效。经典断裂力学描述了拉伸裂纹的运动,它将释放的弹性能耗散在裂纹尖端的点状区域内。在这个框架内,“经典”拉伸裂纹不会超过瑞利波速。利用脆性新虎克材料,我们通过实验证明了“超剪”(supershear)拉伸裂纹的存在,其速度超过剪切波速。

超剪裂纹可平稳加速超过波速,达到接近膨胀波的速度。控制超剪动力学的原理与指导“经典”裂纹的原理不同,这种断裂模式在临界施加应变时被激活。这种非经典的拉伸断裂模式代表了我们对断裂过程理解的根本转变。

Abstract:

Brittle materials fail by means of rapid cracks. Classical fracture mechanics describes the motion of tensile cracks that dissipate released elastic energy within a point-like zone at their tips. Within this framework, a “classical” tensile crack cannot exceed the Rayleigh wave speed, cR. Using brittle neo-hookean materials, we experimentally demonstrate the existence of “supershear” tensile cracks that exceed shear wave speeds, cR. Supershear cracks smoothly accelerate beyond cR, to speeds that could approach dilatation wave speeds. Supershear dynamics are governed by different principles than those guiding “classical” cracks; this fracture mode is excited at critical (material dependent) applied strains. This nonclassical mode of tensile fracture represents a fundamental shift in our understanding of the fracture process.

语言学Linguistics

Language trees with sampled ancestors support a hybrid model for the origin of Indo-European languages

祖先样本语言树支持印欧语系起源的混合模型

作者:PAUL HEGGARTY, CORMAC ANDERSON et al.

链接:

https://www.science.org/doi/full/10.1126/science.abg0818

摘要:

印欧语系的起源一直备受争议。核心词汇的贝叶斯系统发育分析得出了相互矛盾的结果。有些人支持在距今9000年前从安纳托利亚随着农业扩展,另一些人则支持是在公元前6000年从东欧大草原随着以马为基础的畜牧业传播出去的观点。

在此,我们提出了一个消除过去在同源编码中不一致的、更广泛的印欧核心词汇数据库。对该数据集的系统发育分析表明,极少有古代语言是现代进化枝的直系祖先,同时,我们得出该家族的根年龄约为8120年。虽然这个时间与草原假说不一致,但不排除高加索以南存在起源地,随后其分支向北延伸到草原,之后扩散穿过欧洲。

我们将这种杂交假设与最近发表的来自草原和新月沃土北方的古代DNA证据进行了调和。

Abstract:

The origins of the Indo-European language family are hotly disputed. Bayesian phylogenetic analyses of core vocabulary have produced conflicting results, with some supporting a farming expansion out of Anatolia ~9000 years before present (yr B.P.), while others support a spread with horse-based pastoralism out of the Pontic-Caspian Steppe ~6000 yr B.P. Here we present an extensive database of Indo-European core vocabulary that eliminates past inconsistencies in cognate coding. Ancestry-enabled phylogenetic analysis of this dataset indicates that few ancient languages are direct ancestors of modern clades and produces a root age of ~8120 yr B.P. for the family. Although this date is not consistent with the Steppe hypothesis, it does not rule out an initial homeland south of the Caucasus, with a subsequent branch northward onto the steppe and then across Europe. We reconcile this hybrid hypothesis with recently published ancient DNA evidence from the steppe and the northern Fertile Crescent.

From language development to language evolution: A unified view of human lexical creativity

从语言发展到语言进化:人类词汇创造的统一视角

作者:THOMAS BROCHHAGEN, GEMMA BOLEDA et al.

链接:

https://www.science.org/doi/full/10.1126/science.ade7981

摘要:

人类语言的一个特征是能通过词义引申来表达多重意义这一创造性用法。这种词汇创造性表现在不同的时间尺度上,从儿童时期的语言发展到词义的历史演变。我们探讨了词汇创造力的不同表现形式是否存在一个共同基础。

使用计算模型,我们展示了一组简约的语义知识类型,这些类型表征了跨越1400多种语言的发展数据以及意义扩展的进化产物。

进化数据模型很好地解释了发育数据,反之亦然。这些发现表明,人类词汇创造力有一个统一的基础,同时存在于个体的短暂产物和跨语言系统发生的进化产物中。

Abstract:

A defining property of human language is the creative use of words to express multiple meanings through word meaning extension. Such lexical creativity is manifested at different timescales, ranging from language development in children to the evolution of word meanings over history. We explored whether different manifestations of lexical creativity build on a common foundation. Using computational models, we show that a parsimonious set of semantic knowledge types characterize developmental data as well as evolutionary products of meaning extension spanning over 1400 languages. Models for evolutionary data account very well for developmental data, and vice versa. These findings suggest a unified foundation for human lexical creativity underlying both the fleeting products of individual ontogeny and the evolutionary products of phylogeny across languages.

生物学Biology

Deploying synthetic coevolution and machine learning to engineer protein-protein interactions

利用合成协同进化和机器学习设计蛋白质-蛋白质相互作用

作者:AERIN YANG, KEVIN M. JUDE et al.

链接:

https://www.science.org/doi/full/10.1126/science.adh1720

摘要:

蛋白质-蛋白质相互作用的微调通过协同进化而自然发生,但这一过程很难在实验室中重现。我们描述了一个合成蛋白质-蛋白质协同进化的平台,可以从复合体库中分离出相互作用的匹配对的突变蛋白。

这个共同进化复合物的大型数据集推动了对Z结构域-粘附体对之间的分子识别的系统级分析,涵盖了广泛的结构、亲和性、交叉反应性和正交性,并捕获了广泛的共同进化网络。此外,我们利用预训练的蛋白质语言模型来扩大我们的协同进化屏幕的氨基酸多样性,据预测重塑的界面将超出实验库范围。

Abstract:

Fine-tuning of protein-protein interactions occurs naturally through coevolution, but this process is difficult to recapitulate in the laboratory. We describe a platform for synthetic protein-protein coevolution that can isolate matched pairs of interacting muteins from complex libraries. This large dataset of coevolved complexes drove a systems-level analysis of molecular recognition between Z domain–affibody pairs spanning a wide range of structures, affinities, cross-reactivities, and orthogonalities, and captured a broad spectrum of coevolutionary networks. Furthermore, we harnessed pretrained protein language models to expand, in silico, the amino acid diversity of our coevolution screen, predicting remodeled interfaces beyond the reach of the experimental library.

TRIM11 protects against tauopathies and is down-regulated in Alzheimer’s disease

TRIM11可以防止tau蛋白病变,并在阿尔茨海默病患者的大脑中显示下调

作者:ZI-YANG ZHANG, DILSHAN S. HARISCHANDRA et al.

链接:

https://www.science.org/doi/full/10.1126/science.add6696

摘要:

在这里,通过系统地分析人类TRIMs蛋白,我们发现了一些TRIMs可以有效地抑制tau蛋白聚集。其中TRIM11在阿尔茨海默病患者的大脑中显著下调。TRIM11促进突变型tau蛋白和多余的正常tau蛋白的蛋白酶体降解。它还通过作为分子伴侣来防止tau蛋白错误折叠,和分解酶来溶解预先形成的tau蛋白原纤维以增强其溶解性。

TRIM11维持神经元的连通性和活力。在多种tau蛋白病动物模型中,通过腺相关病毒颅内递送TRIM11可改善病理、神经炎症和认知障碍。这些结果表明,TRIM11下调有助于tau蛋白病的发病机制,恢复TRIM11的表达可能是一种有效的治疗策略。

Abstract:

Here, by systematically analyzing human tripartite motif (TRIM) proteins, we identified a few TRIMs that could potently inhibit tau aggregation. Among them, TRIM11 was markedly down-regulated in AD brains. TRIM11 promoted the proteasomal degradation of mutant tau as well as superfluous normal tau. It also enhanced tau solubility by acting as both a molecular chaperone to prevent tau misfolding and a disaggregase to dissolve preformed tau fibrils. TRIM11 maintained the connectivity and viability of neurons. Intracranial delivery of TRIM11 through adeno-associated viruses ameliorated pathology, neuroinflammation, and cognitive impairments in multiple animal models of tauopathies. These results suggest that TRIM11 down-regulation contributes to the pathogenesis of tauopathies and that restoring TRIM11 expression may represent an effective therapeutic strategy.

 
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