前沿速递 | NCS 集萃: 2025-04-10 期 [Up]

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『Abstract』Human pelvic evolution following the human-chimpanzee divergence is thought to result in an obstetrical dilemma, a mismatch between large infant brains and narrowed female birth canals, but empirical evidence has been equivocal. By using deep learning on 31,115 dual-energy x-ray absorptiometry scans from UK Biobank, we identified 180 loci associated with seven highly heritable pelvic phenotypes. Birth canal phenotypes showed sex-specific genetic architecture, aligning with reproductive function. Larger birth canals were linked to slower walking pace and reduced back pain but increased hip osteoarthritis risk, whereas narrower birth canals were associated with reduced pelvic floor disorder risk but increased obstructed labor risk. Lastly, genetic correlation between birth canal and head widths provides evidence of coevolution between the human pelvis and brain, partially mitigating the dilemma.

『摘要』 人类与黑猩猩分道扬镳后,人类骨盆的进化被认为导致了产科困境,即婴儿大脑较大与女性产道狭窄之间的不匹配,但实证证据一直模棱两可。我们通过对英国生物样本库中的31115份双能X射线吸收测定法进行深度学习,确定了与七种高度遗传的骨盆表型相关的180个基因位点。产道表型显示出与生殖功能一致的性别特异性遗传结构。较宽的产道与较慢的步行速度和较低的背痛相关,但会增加髋关节骨关节炎的风险,而较窄的产道与较低的盆底功能障碍风险相关,但会增加难产的风险。最后,产道宽度和头部宽度之间的遗传相关性为人类骨盆和大脑的协同进化提供了证据,这在一定程度上缓解了上述困境。
『总结』 研究发现人类骨盆进化与180个基因位点相关,产道宽度影响多种健康状况,且产道与头部宽度的遗传相关性表明人类骨盆和大脑存在协同进化。
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『Abstract』Electrostatic dielectric capacitors with ultrahigh power densities are sought after for advanced electronic and electrical systems owing to their ultrafast charge-discharge capability. However, low energy density resulting from low breakdown strength and suppressed polarization still remains a daunting challenge for practical applications. We propose a microstructural strategy with dendritic nanopolar (DNP) regions self-assembled into an insulator, which simultaneously enhances breakdown strength and high-field polarizability and minimizes energy loss and thus markedly improves energy storage performance and stability. For illustration, in this study, we achieved a high energy density of 215.8 joules per cubic centimeter with an efficiency of 80.7% at a high electric field of 7.4 megavolts per centimeter in a DNP structure–designed PbZr 0.53 Ti 0.47 O 3 -MgO film. The proposed strategy is generally applicable for development of high-performance dielectric microcapacitors.

『摘要』 静电介电电容器由于具有超快的充放电能力,在先进电子电气系统中备受追捧。然而,由于击穿强度低和极化受限导致的低能量密度仍是实际应用中的一大难题。我们提出了一种微观结构策略,即让树枝状纳米极区(DNP)在绝缘体中自组装,这种策略能同时提高击穿强度和高场极化率,并将能量损失降至最低,从而显著提高储能性能和稳定性。在本研究中,我们以DNP结构设计的PbZr 0.53 Ti 0.47 O 3 -MgO薄膜为例,在7.4兆伏每厘米的高电场下实现了215.8焦耳每立方厘米的高能量密度,效率为80.7%。该策略普遍适用于高性能介电微型电容器的开发。
『总结』 通过树枝状纳米极区在绝缘体中自组装的策略,显著提高了电容器的储能性能和稳定性,实现了高能量密度。
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『Abstract』Despite the growing threat of pharmaceutical pollution, we lack an understanding of whether and how such pollutants influence animal behavior in the wild. Using laboratory- and field-based experiments across multiple years in Atlantic salmon ( Salmo salar ; n = 730), we show that the globally detected anxiolytic pollutant clobazam accumulates in the brain of exposed fish and influences river-to-sea migration success. Clobazam exposure increased the speed with which fish passed through two hydropower dams along their migration route, resulting in more clobazam-exposed fish reaching the sea compared with controls. We argue that such effects may arise from altered shoaling behavior in fish exposed to clobazam. Drug-induced behavioral changes are expected to have wide-ranging consequences for the ecology and evolution of wild populations.

『摘要』 尽管药物污染威胁日益加剧,但我们尚不清楚这类污染物是否会影响以及如何影响野生动物的行为。我们对大西洋鲑鱼(Salmo salar;n=730)进行了为期多年的实验室和野外实验,结果表明,全球范围内已检测到的抗焦虑药物氯巴占会在暴露鱼类的脑部累积,并影响其从河流到海洋的迁徙成功率。接触过氯巴占的鱼穿过其迁徙路线上两座水电站大坝的速度增加,因此相比对照组,更多接触过氯巴占的鱼成功到达海洋。我们认为,这种影响可能源于氯巴占使鱼类的群游行为发生改变。药物诱导的行为变化预计会对野生种群的生态和进化产生广泛影响。
『总结』 研究发现抗焦虑药物氯巴占会累积在鱼类脑部,改变其迁徙行为和成功率,可能对野生种群的生态和进化产生广泛影响。
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『Abstract』T cell priming is characterized by an initial activation phase that involves stable interactions with dendritic cells (DCs). How activated T cells receive the paracrine signals required for their differentiation once they have disengaged from DCs and resumed their migration has been unclear. We identified a distinct priming phase that favors CD8 T cells expressing receptors with high affinity for antigen. CXCR3 expression by CD8 T cells was required for their hours-long reengagement with DCs in specific subfollicular niches in lymph nodes. CD4 T cells paused briefly at the sites of CD8 T cell and DC interactions and provided Interleukin-2 (IL-2) before moving to another DC. Our results highlight a previously unappreciated phase of cell-cell interactions during T cell priming and have direct implications for vaccinations and cellular immunotherapies.

『摘要』 在T细胞启动过程中,初始激活阶段涉及与树突状细胞(DC)的稳定相互作用。然而,T细胞在与DC分离并恢复迁移后,如何接收分化所需的旁分泌信号,这一点一直不明确。我们发现了一个特殊的启动阶段,该阶段有利于表达高亲和力抗原受体的CD8 T细胞。CD8 T细胞表达CXCR3对于它们在淋巴结特定皮下微环境中与DC进行长达数小时的再次结合至关重要。CD4 T细胞在CD8 T细胞与DC相互作用的位置短暂停留,并提供白细胞介素-2(IL-2),然后移动到另一个DC。我们的研究结果突出了T细胞启动过程中一个以前未被重视的细胞间相互作用阶段,这对疫苗接种和细胞免疫疗法具有直接影响。
『总结』 研究发现T细胞启动中存在一个特殊阶段,需要CD8 T细胞通过CXCR3与DC再次结合,CD4 T细胞提供IL-2,这对疫苗和免疫治疗有重要意义。
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『Abstract』Mitochondrial damage is a hallmark of metabolic diseases, including diabetes, yet the consequences of compromised mitochondria in metabolic tissues are often unclear. In this work, we report that dysfunctional mitochondrial quality control engages a retrograde (mitonuclear) signaling program that impairs cellular identity and maturity in β cells, hepatocytes, and brown adipocytes. Targeted deficiency throughout the mitochondrial quality control pathway, including genome integrity, dynamics, or turnover, impaired the oxidative phosphorylation machinery, activating the mitochondrial integrated stress response, eliciting chromatin remodeling, and promoting cellular immaturity rather than apoptosis to yield metabolic dysfunction. Pharmacologic blockade of the integrated stress response in vivo restored β cell identity after the loss of mitochondrial quality control. Targeting mitochondrial retrograde signaling may therefore be promising in the treatment or prevention of metabolic disorders.

『摘要』 线粒体损伤是包括糖尿病在内的代谢性疾病的标志,但代谢组织中线粒体功能受损的后果往往尚不清楚。本研究报告称,线粒体质量控制功能失调会启动一种逆行(线粒体与核之间)信号传导程序,该程序会损害β细胞、肝细胞和棕色脂肪细胞的细胞特性和成熟度。线粒体质量控制通路(包括基因组完整性、动力学或周转)的靶向缺陷会损害氧化磷酸化机制,激活线粒体综合应激反应,引起染色质重塑,并促进细胞不成熟(而非凋亡),从而导致代谢功能障碍。在体内药理学阻断综合应激反应可恢复线粒体质量控制缺失后的β细胞特性。因此,靶向线粒体逆行信号传导在治疗或预防代谢障碍方面可能具有广阔前景。
『总结』 靶向线粒体逆行信号传导或有助于治疗或预防代谢障碍。
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『Abstract』Quantum computers hold the promise of solving certain problems that lie beyond the reach of conventional computers. However, establishing this capability, especially for impactful and meaningful problems, remains a central challenge. Here, we show that superconducting quantum annealing processors can rapidly generate samples in close agreement with solutions of the Schrodinger equation. We demonstrate area-law scaling of entanglement in the model quench dynamics of two-, three-, and infinite-dimensional spin glasses, supporting the observed stretched-exponential scaling of effort for matrix-product-state approaches. We show that several leading approximate methods based on tensor networks and neural networks cannot achieve the same accuracy as the quantum annealer within a reasonable time frame. Thus, quantum annealers can answer questions of practical importance that may remain out of reach for classical computation.

『摘要』 量子计算机有望解决某些传统计算机无法解决的问题。然而,要实现这一能力,尤其是针对那些有重大影响和有意义的问题,仍然是核心挑战。本文表明,超导量子退火处理器可以快速生成与薛定谔方程解高度一致的样本。我们展示了二维、三维和无限维自旋玻璃模型淬火动力学中的纠缠面积定律缩放,这支持了矩阵乘积态方法所观察到的拉伸指数努力缩放。研究表明,基于张量网络和神经网络的几种主流近似方法在合理时间内无法达到与量子退火器相同的精度。因此,量子退火器可以解答具有实际意义的问题,而这些问题可能是传统计算无法解决的。
『总结』 量子退火器能高效生成与薛定谔方程解相符的样本,在解决特定问题上优于传统方法,展现了量子计算在实用问题上的潜力。
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『Abstract』Cachexia, a severe wasting syndrome associated with inflammatory conditions, often leads to multiorgan failure and death. Patients with cachexia experience extreme fatigue, apathy, and clinical depression, yet the biological mechanisms underlying these behavioral symptoms and their relationship to the disease remain unclear. In a mouse cancer model, cachexia specifically induced increased effort-sensitivity, apathy-like symptoms through a cytokine-sensing brainstem-to-basal ganglia circuit. This neural circuit detects elevated interleukin-6 (IL-6) at cachexia onset and translates inflammatory signals into decreased mesolimbic dopamine, thereby increasing effort sensitivity. We alleviated these apathy-like symptoms by targeting key circuit nodes: administering an anti–IL-6 antibody treatment, ablating cytokine sensing in the brainstem, and optogenetically or pharmacologically boosting mesolimbic dopamine. Our findings uncovered a central neural circuit that senses systemic inflammation and orchestrates behavioral changes, providing mechanistic insights into the connection between chronic inflammation and depressive symptoms.

『摘要』 恶病质是一种与炎症相关的严重消耗性综合征,常导致多器官衰竭和死亡。恶病质患者会出现极度疲劳、冷漠和临床抑郁症状,但这些行为症状的生物机制及其与疾病的关系尚不清楚。在小鼠癌症模型中,恶病质通过一种细胞因子感应的脑干至基底神经节回路,特异性地引起努力敏感性增加和类似冷漠的症状。该神经回路在恶病质发生时检测到白介素-6(IL-6)水平升高,并将炎症信号转化为中脑边缘多巴胺减少,从而提高努力敏感性。我们通过靶向关键回路节点来缓解这些类似冷漠的症状:给予抗IL-6抗体治疗、消除脑干中的细胞因子感应,以及通过光遗传学或药理学方法增强中脑边缘多巴胺。我们的研究结果发现了一个感知全身炎症并调节行为变化的中枢神经回路,为慢性炎症与抑郁症状之间的联系提供了机制上的见解。
『总结』 研究表明,特定的中枢神经回路可感知炎症并引发行为变化,揭示了慢性炎症与恶病质患者抑郁症状之间的联系。
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『Abstract』Huanglongbing (HLB) is a devastating citrus disease. In this work, we report an HLB resistance regulatory circuit in Citrus composed of an E3 ubiquitin ligase, PUB21, and its substrate, the MYC2 transcription factor, which regulates jasmonate-mediated defense responses. A helitron insertion in the PUB21 promoter introduced multiple MYC2-binding cis-elements to create a regulatory circuit linking the PUB21 activity with MYC2 degradation. Ectopic expression of a natural dominant-negative PUB21 paralog discovered in distant Citrus relatives stabilized MYC2 and conferred resistance to HLB. Antiproteolysis peptides (APPs), identified by artificial intelligence, stabilized MYC2 by binding and inhibiting PUB21 activity. A 14–amino acid peptide, APP3-14, molecularly controlled HLB in greenhouse and field trials. This approach represents a strategy to combat uncultivable pathogens through targeted disease resistance protein stabilization.

『摘要』 黄龙病(HLB)是一种毁灭性的柑橘类疾病。本研究报道了柑橘中一种由E3泛素连接酶PUB21及其底物MYC2转录因子组成的黄龙病抗性调控回路,该回路可调节茉莉酸介导的防御反应。PUB21启动子中的一个螺旋插入序列引入了多个MYC2结合顺式元件,从而形成了一个将PUB21活性与MYC2降解联系起来的调控回路。在远缘柑橘亲本中发现的一种天然显性负性PUB21旁系同源物的异位表达稳定了MYC2并赋予了对黄龙病的抗性。通过人工智能鉴定出的抗蛋白水解肽(APP)可通过结合并抑制PUB21活性来稳定MYC2。一种包含14个氨基酸的肽APP3-14在温室和田间试验中从分子层面控制了黄龙病。该方法是通过靶向稳定抗病蛋白来对抗不可培养病原体的策略。
『总结』 研究发现柑橘中PUB21-MYC2调控回路可调控黄龙病抗性,且通过稳定MYC2的肽APP3-14有效控制了黄龙病。
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『Abstract』The arrangement of genes along bacterial chromosomes influences their expression through growth rate–dependent gene copy number changes during DNA replication. Although translation- and transcription-related genes often cluster near the origin of replication, the extent of positional biases across gene families remains unclear. We hypothesized that natural selection broadly favors specific chromosomal positions to optimize growth rate–dependent expression. Analyzing 910 bacterial species and proteomics data from Escherichia coli and Bacillus subtilis , we found that about two-thirds of bacterial gene families are positionally biased. Natural selection drives genes mainly toward the origin or terminus of replication, with the strongest selection in fast-growing species. Our findings reveal chromosomal positioning as a fundamental mechanism for coordinating gene expression with growth rate, highlighting evolutionary constraints on bacterial genome architecture.

『摘要』 在DNA复制过程中,细菌染色体上基因的排列会通过依赖于生长速率的基因拷贝数变化来影响其表达。尽管与翻译和转录相关的基因通常聚集在复制起点附近,但基因家族之间的位置偏好的程度仍不清楚。我们假设自然选择普遍倾向于特定的染色体位置,以优化依赖于生长速率的表达。通过分析910种细菌物种以及大肠杆菌和枯草芽孢杆菌的蛋白质组学数据,我们发现约三分之二的细菌基因家族存在位置偏好。自然选择主要驱使基因向复制起点或终点移动,在快速生长的物种中这种选择最为强烈。我们的研究结果揭示了染色体定位是协调基因表达与生长速率的基本机制,突出了细菌基因组结构的进化限制。
『总结』 研究发现细菌基因在染色体上的位置偏好是协调基因表达与生长速率的基本机制,且自然选择主要驱使基因定位在复制起点或终点。
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『Abstract』One approach for closed-loop plastics recycling relies on reverting polymers back into monomers because one can then make new plastics without loss of properties. This depolymerization requirement restricts the molecular design to making polymers with high mechanical performance. We report a three-dimensional (3D) printing chemistry through stepwise photopolymerization by forming dithioacetal bonds. The polymerized network can be transformed back into a photoreactive oligomer by dissociation of the dithioacetal bonds. This network-oligomer transformation is reversible, therefore allowing circular 3D printing using the same material. Our approach offers the flexibility of making modular adjustments in the design of the network backbone of a polymer. This allows access to fully recyclable elastomers, crystalline polymers, and rigid glassy polymers with high mechanical toughness, making them potentially suitable for diverse applications.

『摘要』 一种闭环塑料回收方法依赖于将聚合物还原为单体,因为这样可以在不损失性能的情况下制造新塑料。这种解聚需求限制了分子设计,使其只能用于生产具有高机械性能的聚合物。本文报告了一种通过分步光聚合形成二硫缩醛键的3D打印化学方法。聚合网络可以通过二硫缩醛键的解离转化回光反应性低聚物。这种网络-低聚物转化是可逆的,因此可以使用同一种材料进行循环3D打印。本文提出的方法在对聚合物网络主链的设计进行模块化调整方面具有灵活性。这使得可以生产完全可回收的弹性体、结晶聚合物以及具有高机械韧性的刚性玻璃态聚合物,从而使它们有可能适用于多种用途。
『总结』 本研究开发了一种基于二硫缩醛键分步光聚合的3D打印技术,该技术实现了聚合网络与低聚物间的可逆转化,能够生产出多种高性能且完全可回收的聚合物。
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『Abstract』That neutrinos carry a nonvanishing rest mass is evidence of physics beyond the Standard Model of elementary particles. Their absolute mass holds relevance in fields from particle physics to cosmology. We report on the search for the effective electron antineutrino mass with the KATRIN experiment. KATRIN performs precision spectroscopy of the tritium β-decay close to the kinematic endpoint. On the basis of the first five measurement campaigns, we derived a best-fit value of m ν 2 = − 0.14 − 0.15 + 0.13 eV , resulting in an upper limit of m ν < 0.45 eV at 90% confidence level. Stemming from 36 million electrons collected in 259 measurement days, a substantial reduction of the background level, and improved systematic uncertainties, this result tightens KATRIN’s previous bound by a factor of almost two.

『摘要』 中微子携带非零静质量是基本粒子标准模型之外物理学的证据。中微子的绝对质量与从粒子物理学到宇宙学的多个领域都息息相关。本文报道了卡特里娜(KATRIN)实验对有效电子反中微子质量的探索。KATRIN对接近运动学终点的氚β衰变进行了精密光谱测量。根据前五次测量活动,我们得出了最佳拟合值mν2=−0.14+0.13−0.15eV,从而在90%的置信水平下得出mν<0.45 eV的上限。这一结果基于在259个测量日内收集的3600万个电子,实现了背景水平的显著降低和系统不确定性的改进,使KATRIN之前的结果界限缩小了近两倍。
『总结』 KATRIN实验通过精密测量氚β衰变,得出了电子反中微子质量上限为0.45 eV(90%置信水平),比之前的结果提高了近两倍。
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『Abstract』The class III phosphatidylinositol-3 kinase complexes I and II (PI3KC3-C1 and PI3KC3-C2) have vital roles in macroautophagy and endosomal maturation, respectively. We elucidated a structural pathway of enzyme activation through cryo–electron microscopy analysis of PI3KC3-C1. The inactive conformation of the VPS15 pseudokinase stabilizes the inactive conformation, sequestering its N -myristate in the N-lobe of the pseudokinase. Upon activation, the myristate is liberated such that the VPS34 lipid kinase catalyzes phosphatidylinositol-3 phosphate production on membranes. The VPS15 pseudokinase domain binds tightly to guanosine triphosphate and stabilizes a web of interactions to autoinhibit the cytosolic complex and promote activation upon membrane binding. These findings show in atomistic detail how the VPS34 lipid kinase is activated in the context of a complete PI3K complex.

『摘要』 III类磷脂酰肌醇-3激酶复合物I和II(PI3KC3-C1和PI3KC3-C2)分别在巨自噬和核内体成熟过程中发挥着至关重要的作用。我们通过冷冻电子显微镜分析PI3KC3-C1,阐明了酶活化的结构途径。VPS15假激酶的非活化构象稳定了这种非活化状态,将其N-肉豆蔻酰基隐藏在假激酶的N-叶中。在活化时,肉豆蔻酰基被释放,使得VPS34脂激酶能够在膜上催化磷脂酰肌醇-3-磷酸的产生。VPS15假激酶结构域与三磷酸鸟苷紧密结合,稳定了一系列相互作用,以自抑制胞质溶胶复合物,并促进与膜结合时的活化。这些研究结果从原子层面详细阐述了在完整的PI3K复合物中VPS34脂激酶是如何被活化的。
『总结』 本研究揭示了PI3KC3-C1中VPS34脂激酶通过特定的结构途径在完整PI3K复合物中被活化的机制。
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『Abstract』Variants in GBA1 resulting in decreased lysosomal glucocerebrosidase (GCase) activity are a common risk factor for Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). Incomplete penetrance of GBA1 variants suggests that additional genes contribute to PD and DLB manifestation. By using a pooled genome-wide CRISPR interference screen, we identified copper metabolism MURR1 domain–containing 3 (COMMD3) protein, a component of the COMMD/coiled-coil domain–containing protein 22 (CCDC22)/CCDC93 (CCC) and Commander complexes, as a modifier of GCase and lysosomal activity. Loss of COMMD3 increased the release of lysosomal proteins through extracellular vesicles, leading to their impaired delivery to endolysosomes and consequent lysosomal dysfunction. Rare variants in the Commander gene family were associated with increased PD risk. Thus, COMMD genes and related complexes regulate lysosomal homeostasis and may represent modifiers in PD and other neurodegenerative diseases associated with lysosomal dysfunction.

『摘要』 GBA1基因变异导致溶酶体葡糖脑苷脂酶(GCase)活性降低,是帕金森病(PD)和路易体痴呆(DLB)的常见风险因素。GBA1基因变异的不完全外显率表明,其他基因也参与了PD和DLB的发病。我们通过集合性全基因组CRISPR干扰筛选,确定了含铜代谢MURR1结构域的3(COMMD3)蛋白是GCase和溶酶体活性的修饰因子,该蛋白是COMMD/含卷曲螺旋结构域蛋白22(CCDC22)/CCDC93(CCC)和Commander复合物的组分。COMMD3缺失会增加溶酶体蛋白通过细胞外囊泡的释放,导致其向核内体-溶酶体的输送受损,并因此导致溶酶体功能障碍。Commander基因家族中的罕见变异与PD风险增加相关。因此,COMMD基因及相关复合物可调节溶酶体稳态,并可能是PD和其他与溶酶体功能障碍相关的神经退行性疾病的修饰因子。
『总结』 研究发现COMMD3是GCase和溶酶体活性的修饰因子,其与溶酶体功能障碍相关的神经退行性疾病风险增加有关。
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『Abstract』Denisovans are an extinct hominin group defined by ancient genomes of Middle to Late Pleistocene fossils from southern Siberia. Although genomic evidence suggests their widespread distribution throughout eastern Asia and possibly Oceania, so far only a few fossils from the Altai and Tibet are confidently identified molecularly as Denisovan. We identified a hominin mandible (Penghu 1) from Taiwan (10,000 to 70,000 years ago or 130,000 to 190,000 years ago) as belonging to a male Denisovan by applying ancient protein analysis. We retrieved 4241 amino acid residues and identified two Denisovan-specific variants. The increased fossil sample of Denisovans demonstrates their wider distribution, including warm and humid regions, as well as their shared distinct robust dentognathic traits that markedly contrast with their sister group, Neanderthals.

『摘要』 迪尼索万人是一种已灭绝的人属群体,其定义来自西伯利亚南部中晚更新世化石的古代基因组。尽管基因组证据表明他们在东亚乃至大洋洲广泛分布,但到目前为止,仅阿尔泰山和西藏的少数化石在分子层面上被确信为迪尼索万人。我们通过古代蛋白质分析,将来自台湾(距今1万至7万年或13万至19万年)的一块人属下颌骨(澎湖1)鉴定为属于一名迪尼索万男性。我们检索到4241个氨基酸残基,并鉴定出两种迪尼索万特有的变体。迪尼索万化石样本的增加表明了他们分布范围更广,包括温暖潮湿的地区,而且他们共有的明显健壮的齿颌特征与他们的姊妹群体——尼安德特人形成鲜明对比。
『总结』 研究发现台湾一块人属下颌骨属于迪尼索万人,表明迪尼索万分布范围广泛且具有独特的齿颌特征。
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『Abstract』We used Hi-C, imaging, proteomics, and polymer modeling to define rules of engagement for SMC (structural maintenance of chromosomes) complexes as cells refold interphase chromatin into rod-shaped mitotic chromosomes. First, condensin disassembles interphase chromatin loop organization by evicting or displacing extrusive cohesin. Second, condensin bypasses cohesive cohesins, thereby maintaining sister chromatid cohesion as sisters separate. Studies of mitotic chromosomes formed by cohesin, condensin II, and condensin I alone or in combination lead to refined models of mitotic chromosome conformation. In these models, loops are consecutive and not overlapping, implying that condensins stall upon encountering each other. The dynamics of Hi-C interactions and chromosome morphology reveal that during prophase, loops are extruded in vivo at ∼1 to 3 kilobases per second by condensins as they form a disordered discontinuous helical scaffold within individual chromatids.

『摘要』 我们利用Hi-C技术、成像技术、蛋白质组学和聚合物建模,定义了细胞将间期染色质折叠成杆状有丝分裂染色体时,SMC(染色体结构维持)复合物的参与规则。首先,凝聚素通过驱逐或取代突出的黏连蛋白,从而拆解间期染色质的环状组织。其次,凝聚素绕过具有黏连性的黏连蛋白,从而在姐妹染色单体分离时保持其黏连。单独或组合使用黏连蛋白、凝聚素II和凝聚素I形成的有丝分裂染色体的研究,得出了有丝分裂染色体构象的精细模型。在这些模型中,环状结构是连续的,不重叠,这意味着凝聚素在遇到彼此时会停滞。Hi-C相互作用和染色体形态的动力学表明,在前期,凝聚素在单个染色单体内部形成一个无序的不连续螺旋支架时,会在体内以每秒约1至3千碱基的速度挤出环状结构。
『总结』 本研究利用多种技术揭示了SMC复合物在细胞将间期染色质折叠成有丝分裂染色体过程中的作用规则,发现了凝聚素和黏连蛋白的相互作用机制以及染色体环状结构的形成和动力学特征。
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『Abstract』Mammalian genomes are folded through the distinct actions of structural maintenance of chromosome (SMC) complexes, which include the chromatin loop-extruding cohesin (extrusive cohesin), the sister chromatid cohesive cohesin and the mitotic chromosome-associated condensins . Although these complexes function at different stages of the cell cycle, they exist together on chromatin during the G2-to-M phase transition, when the genome structure undergoes substantial reorganization . Yet, how the different SMC complexes affect each other and how their interactions orchestrate the dynamic folding of the three-dimensional genome remain unclear. Here we engineered all possible cohesin and condensin configurations on mitotic chromosomes to delineate the concerted, mutually influential action of SMC complexes. We show that condensin disrupts the binding of extrusive cohesin at CCCTC-binding factor (CTCF) sites, thereby promoting the disassembly of interphase topologically associating domains (TADs) and loops during mitotic progression. Conversely, extrusive cohesin impedes condensin-mediated mitotic chromosome spiralization. Condensin reduces peaks of cohesive cohesin, whereas cohesive cohesin antagonizes condensin-mediated longitudinal shortening of mitotic chromosomes. The presence of both extrusive and cohesive cohesin synergizes these effects and inhibits mitotic chromosome condensation. Extrusive cohesin positions cohesive cohesin at CTCF-binding sites. However, cohesive cohesin by itself cannot be arrested by CTCF molecules and is insufficient to establish TADs or loops. Moreover, it lacks loop-extrusion capacity, which indicates that cohesive cohesin has nonoverlapping functions with extrusive cohesin. Finally, cohesive cohesin restricts chromatin loop expansion mediated by extrusive cohesin. Collectively, our data describe a three-way interaction among major SMC complexes that dynamically modulates chromatin architecture during cell cycle progression.

『摘要』 哺乳动物的基因组通过染色体结构维持(SMC)复合体的不同作用而折叠,这些复合体包括染色质环挤出黏连蛋白(挤出黏连蛋白)、姐妹染色单体黏连蛋白和与有丝分裂染色体相关的凝聚蛋白。尽管这些复合体在细胞周期的不同阶段发挥作用,但在G2期至M期转换过程中,它们共同存在于染色质上,此时基因组结构会发生重大重组。然而,不同的SMC复合体如何相互影响,以及它们的相互作用如何协调三维基因组的动态折叠,目前尚不清楚。本研究构建了有丝分裂染色体上所有可能的黏连蛋白和凝聚蛋白配置,以阐述SMC复合体的协同和相互影响作用。我们发现,凝聚蛋白会破坏挤出黏连蛋白在CCCTC结合因子(CTCF)位点的结合,从而促进有丝分裂过程中间期拓扑关联域(TADs)和环的解离。相反,挤出黏连蛋白会阻碍凝聚蛋白介导的有丝分裂染色体螺旋化。凝聚蛋白会减少黏连蛋白的峰值,而黏连蛋白则拮抗凝聚蛋白介导的有丝分裂染色体纵向缩短。挤出黏连蛋白和黏连蛋白的同时存在会协同这些效应并抑制有丝分裂染色体凝集。挤出黏连蛋白将黏连蛋白定位在CTCF结合位点上。然而,黏连蛋白本身不能被CTCF分子阻滞,也不足以建立TADs或环。此外,它缺乏环挤出能力,这表明黏连蛋白与挤出黏连蛋白的功能不重叠。最后,黏连蛋白限制挤出黏连蛋白介导的染色质环扩张。总的来说,本研究数据描述了主要的SMC复合体之间的三元相互作用,这种相互作用在细胞周期进程中动态调节染色质结构。
『总结』 本研究揭示了SMC复合体(包括挤出黏连蛋白、黏连蛋白和凝聚蛋白)在细胞周期中的三元相互作用,及其对染色质结构动态调节的机制。
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『Abstract』Trees are an important carbon sink as they accumulate biomass through photosynthesis . Identifying tree species that grow fast is therefore commonly considered to be essential for effective climate change mitigation through forest planting. Although species characteristics are key information for plantation design and forest management, field studies often fail to detect clear relationships between species functional traits and tree growth . Here, by consolidating four independent datasets and classifying the acquisitive and conservative species based on their functional trait values, we show that acquisitive tree species, which are supposedly fast-growing species, generally grow slowly in field conditions. This discrepancy between the current paradigm and field observations is explained by the interactions with environmental conditions that influence growth. Acquisitive species require moist mild climates and fertile soils, conditions that are generally not met in the field. By contrast, conservative species, which are supposedly slow-growing species, show generally higher realized growth due to their ability to tolerate unfavourable environmental conditions. In general, conservative tree species grow more steadily than acquisitive tree species in non-tropical forests. We recommend planting acquisitive tree species in areas where they can realize their fast-growing potential. In other regions, where environmental stress is higher, conservative tree species have a larger potential to fix carbon in their biomass.

『摘要』 树木是重要的碳汇,因为它们通过光合作用积累生物质。因此,识别生长迅速的树种通常被认为是通过植树造林有效减缓气候变化的关键。虽然物种特性是造林设计和森林管理的重要信息,但现场研究往往无法明确物种功能性状与树木生长之间的关系。本研究整合了四个独立的数据集,并根据功能性状值将物种分为获取型物种和保守型物种,结果表明,被假定为生长迅速的获取型树种在实地条件下通常生长缓慢。当前范例与实地观测之间的差异可通过影响生长的环境条件的相互作用来解释。获取型物种需要湿润温和的气候和肥沃的土壤,而这些条件在实地通常无法满足。相反,被假定为生长缓慢的保守型物种由于其能够耐受不利的环境条件,通常表现出更高的实际生长速度。总体而言,在非热带森林中,保守型树种的生长比获取型树种更为稳定。我们建议在能发挥其快速生长潜力的地区种植获取型树种。而在环境压力较大的其他地区,保守型树种在其生物质中固定碳的潜力更大。
『总结』 研究发现获取型树种在实地条件下生长缓慢,保守型树种更能耐受不利环境,建议根据环境条件选择合适的树种以有效固碳。
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『Abstract』The complexity of neural circuits makes it challenging to decipher the brain’s algorithms of intelligence. Recent breakthroughs in deep learning have produced models that accurately simulate brain activity, enhancing our understanding of the brain’s computational objectives and neural coding. However, it is difficult for such models to generalize beyond their training distribution, limiting their utility. The emergence of foundation models trained on vast datasets has introduced a new artificial intelligence paradigm with remarkable generalization capabilities. Here we collected large amounts of neural activity from visual cortices of multiple mice and trained a foundation model to accurately predict neuronal responses to arbitrary natural videos. This model generalized to new mice with minimal training and successfully predicted responses across various new stimulus domains, such as coherent motion and noise patterns. Beyond neural response prediction, the model also accurately predicted anatomical cell types, dendritic features and neuronal connectivity within the MICrONS functional connectomics dataset . Our work is a crucial step towards building foundation models of the brain. As neuroscience accumulates larger, multimodal datasets, foundation models will reveal statistical regularities, enable rapid adaptation to new tasks and accelerate research.

『摘要』 神经电路的复杂性使得破译大脑的智能算法具有挑战性。深度学习领域的最新突破产生了能够准确模拟大脑活动的模型,从而增强了我们对大脑计算目标和神经编码的理解。然而,这类模型很难在其训练分布之外进行泛化,因此其应用受到限制。基于庞大数据集训练的基础模型的出现,引入了一种具有显著泛化能力的新型人工智能范式。在本研究中,我们从多只小鼠的视觉皮层中收集了大量神经活动数据,并训练了一个基础模型来准确预测神经元对任意自然视频的响应。该模型仅需少量训练即可泛化到新的小鼠,并成功预测了各种新刺激域(如连贯运动和噪声模式)的响应。除了神经响应预测外,该模型还准确预测了MICrONS功能连接组数据集中的解剖细胞类型、树突特征和神经元连接性。我们的工作是构建大脑基础模型的关键一步。随着神经科学积累更多更大规模、多模态的数据集,基础模型将揭示统计规律,实现快速适应新任务,并加速相关研究。
『总结』 本研究通过训练基础模型准确预测小鼠视觉皮层神经元对自然视频的响应,展示了在神经科学中应用大型数据集和人工智能技术的潜力。
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『Abstract』Although quantum computers can perform a wide range of practically important tasks beyond the abilities of classical computers , realizing this potential remains a challenge. An example is to use an untrusted remote device to generate random bits that can be certified to contain a certain amount of entropy . Certified randomness has many applications but is impossible to achieve solely by classical computation. Here we demonstrate the generation of certifiably random bits using the 56-qubit Quantinuum H2-1 trapped-ion quantum computer accessed over the Internet. Our protocol leverages the classical hardness of recent random circuit sampling demonstrations : a client generates quantum ‘challenge’ circuits using a small randomness seed, sends them to an untrusted quantum server to execute and verifies the results of the server. We analyse the security of our protocol against a restricted class of realistic near-term adversaries. Using classical verification with measured combined sustained performance of 1.1 × 10 floating-point operations per second across multiple supercomputers, we certify 71,313 bits of entropy under this restricted adversary and additional assumptions. Our results demonstrate a step towards the practical applicability of present-day quantum computers.

『摘要』 尽管量子计算机能够执行许多超出经典计算机能力的、具有重要实际应用价值的任务,但要实现这一潜力仍然面临挑战。一个例子是利用不受信任的远程设备生成可被认证包含一定熵量的随机比特。经过认证的随机性在许多领域都有应用,但仅凭经典计算无法实现。在这里,我们展示了如何使用通过互联网访问的56量子比特Quantinuum H2-1囚禁离子量子计算机生成可认证的随机比特。我们的协议利用了近期随机电路采样演示中的经典硬度:客户端使用一个小随机种子生成量子“挑战”电路,将其发送到不受信任的量子服务器以执行并验证服务器的结果。我们分析了该协议在应对一类受限的、实际存在的近期对手时的安全性。使用经典验证方法,结合多台超级计算机的持续性能,测得综合性能为每秒1.1×10次浮点运算,我们在此受限对手和额外假设下认证了71313比特熵。我们的研究结果表明,目前的量子计算机距离实际应用又迈进了一步。
『总结』 该研究使用56量子比特的Quantinuum H2-1囚禁离子量子计算机,通过互联网生成了可认证的随机比特,为量子计算机的实际应用迈出了一步。
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『Abstract』Mammalian neocortex contains a highly diverse set of cell types. These cell types have been mapped systematically using a variety of molecular, electrophysiological and morphological approaches . Each modality offers new perspectives on the variation of biological processes underlying cell-type specialization. Cellular-scale electron microscopy provides dense ultrastructural examination and an unbiased perspective on the subcellular organization of brain cells, including their synaptic connectivity and nanometre-scale morphology. In data that contain tens of thousands of neurons, most of which have incomplete reconstructions, identifying cell types becomes a clear challenge for analysis . Here, to address this challenge, we present a systematic survey of the somatic region of all cells in a cubic millimetre of cortex using quantitative features obtained from electron microscopy. This analysis demonstrates that the perisomatic region is sufficient to identify cell types, including types defined primarily on the basis of their connectivity patterns. We then describe how this classification facilitates cell-type-specific connectivity characterization and locating cells with rare connectivity patterns in the dataset.

『摘要』 哺乳动物的新皮层包含多种不同类型的细胞。这些细胞类型已通过各种分子、电生理和形态学方法得到了系统研究。每种方法都为探究细胞类型特化所涉及的生物过程变化提供了新的视角。细胞尺度的电子显微镜能够对脑细胞(包括其突触连接和纳米级形态)的亚细胞结构进行详尽观察并提供无偏见的视角。在包含数万个神经元(其中大多数重建不完整)的数据中,细胞类型的识别成为分析中的一项明显挑战。为解决这一挑战,本文利用电子显微镜获得的定量特征,对皮质立方毫米内所有细胞的胞体区进行了系统调查。分析表明,胞周区足以用于识别细胞类型,包括那些主要根据连接模式定义的细胞类型。然后,本文描述了这种分类方法如何促进细胞类型特异性连接的表征,以及在数据集中定位具有罕见连接模式的细胞。
『总结』 本研究利用电子显微镜的定量特征,对皮质立方毫米内细胞的胞体区进行了系统分析,发现胞周区足以识别多种细胞类型,该方法有助于表征细胞类型特异性连接并定位稀有连接模式的细胞。
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『Abstract』The landscapes of somatic mutation in normal cells inform us about the processes of mutation and selection operative throughout life, providing insight into normal ageing and the earliest stages of cancer development . Here, by whole-genome sequencing of 238 microdissections from 30 individuals, including 18 with gastric cancer, we elucidate the developmental trajectories of normal and malignant gastric epithelium. We find that gastric glands are units of monoclonal cell populations that accrue roughly 28 somatic single-nucleotide variants per year, predominantly attributable to endogenous mutational processes. In individuals with gastric cancer, metaplastic glands often show elevated mutation burdens due to acceleration of mutational processes linked to proliferation and oxidative damage. Unusually for normal cells, gastric epithelial cells often carry recurrent trisomies of specific chromosomes, which are highly enriched in a subset of individuals. Surveying 829 polyclonal gastric microbiopsies by targeted sequencing, we find somatic ‘driver’ mutations in a distinctive repertoire of known cancer genes, including ARID1A , ARID1B , ARID2 , CTNNB1 and KDM6A . The prevalence of mutant clones increases with age to occupy roughly 8% of the gastric epithelial lining by age 60 years and is significantly increased by the presence of severe chronic inflammation. Our findings provide insights into intrinsic and extrinsic influences on somatic evolution in the gastric epithelium in healthy, precancerous and malignant states.

『摘要』 对正常细胞中体细胞突变的研究可以揭示一生中突变和选择的过程,为了解正常衰老和癌症发展的最早阶段提供见解。在本研究中,我们对来自30名个体(其中包括18名胃癌患者)的238个显微切割样本进行了全基因组测序,阐明了正常和恶性胃上皮的发育轨迹。我们发现,胃腺是由单克隆细胞群组成的单位,每年累积约28个体细胞单核苷酸变异,这主要是由内源性突变过程引起的。在胃癌患者中,由于与增殖和氧化损伤相关的突变过程加速,化生腺体通常表现出更高的突变负荷。对于正常细胞而言,胃上皮细胞通常携带特定染色体的复发性三体,这在部分个体中高度富集。通过对829个多克隆胃显微活检样本进行靶向测序,我们在一组已知的癌症基因中发现了体细胞“驱动”突变,包括ARID1A、ARID1B、ARID2、CTNNB1和KDM6A。随着年龄的增长,突变克隆的流行率增加,到60岁时约占胃上皮内衬的8%,并且严重慢性炎症的存在会显著提高其流行率。我们的研究结果为健康、癌前病变和恶性状态下胃上皮体细胞进化的内在和外在影响提供了见解。
『总结』 本研究通过对正常和胃癌细胞的基因组测序,揭示了胃上皮的体细胞突变特征和发育轨迹,为理解正常衰老、炎症及癌症早期的体细胞演化提供了新见解。
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『Abstract』Magnetism typically arises from the effect of exchange interactions on highly localized fermionic wavefunctions in f- and d-atomic orbitals. By contrast, in rhombohedral multilayer graphene (RMG), magnetism—manifesting as spontaneous polarization into one or more spin and valley flavours —originates from itinerant electrons near a Van Hove singularity. Here we show experimentally that the electronic entropy in this system indicates signatures typically associated with disordered local magnetic moments, unexpected for electrons in a fully itinerant metal. Specifically, we find a contribution Δ S ≈ 1 k B per charge carrier that begins at the Curie temperature and survives more than one order of magnitude in temperature. First-order phase transitions show an isospin ‘Pomeranchuk effect’ in which the fluctuating moment phase is entropically favoured over the nearby symmetric Fermi liquid . Our results imply that, despite the itinerant nature of the electron wavefunctions, the spin and valley polarization of individual electrons is decoupled, a phenomenon typically associated with localized moments, as happens, for example, in solid He (ref. ). Transport measurements, surprisingly, show a finite-temperature resistance minimum in the fluctuating moment regime, which we attribute to the interplay of fluctuating magnetic moments and electron–phonon scattering. Our results highlight the universality of soft isospin modes to two-dimensional flat-band systems.

『摘要』 磁性通常源自交换作用对f原子轨道和d原子轨道中高度局域的费米子波函数的影响。相比之下,在菱面体多层石墨烯(RMG)中,磁性表现为自发极化成一种或多种自旋和谷风味,其起源是范霍夫奇点附近的巡游电子。在这里,我们通过实验表明,该系统中的电子熵表现出通常与无序的局部磁矩相关的特征,而这在完全巡游金属中的电子中是意料之外的。具体来说,我们发现每个电荷载流子对熵的贡献ΔS≈1kB,这种贡献从居里温度开始,并在超过一个温度量级范围内持续存在。一阶相变显示出同位旋的“庞加莱克效应”,其中波动矩相在熵上比附近的对称费米液体更有利。我们的研究结果表明,尽管电子波函数具有巡游性,但单个电子的自旋和谷极化是解耦的,这是一种通常与局域磁矩相关的现象,例如,在固体氦中就会发生这种现象(参考文献)。令人惊讶的是,传输测量结果显示,在波动矩状态下,有限温度电阻出现最小值,我们认为这是波动磁矩和电子-声子散射相互作用的结果。我们的研究结果强调了软同位旋模对于二维平带系统的普适性。
『总结』 研究表明,菱面体多层石墨烯中的磁性源于范霍夫奇点附近的巡游电子,且其电子熵表现出与无序局部磁矩相关的特征,揭示了巡游电子系统中自旋和谷极化的解耦现象及软同位旋模的普适性。
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『Abstract』Neural circuit function is shaped both by the cell types that comprise the circuit and the connections between them . Neural cell types have previously been defined by morphology , electrophysiology , transcriptomic expression , connectivity or a combination of such modalities . The Patch-seq technique enables the characterization of morphology, electrophysiology and transcriptomic properties from individual cells . These properties were integrated to define 28 inhibitory, morpho-electric-transcriptomic (MET) cell types in mouse visual cortex , which do not include synaptic connectivity. Conversely, large-scale electron microscopy (EM) enables morphological reconstruction and a near-complete description of a neuron’s local synaptic connectivity, but does not include transcriptomic or electrophysiological information. Here, we leveraged morphological information from Patch-seq to predict the transcriptomically defined cell subclass and/or MET-type of inhibitory neurons within a large-scale EM dataset. We further analysed Martinotti cells—a somatostatin ( Sst )-positive morphological cell type —which were classified successfully into Sst MET-types with distinct axon myelination and synaptic output connectivity patterns. We demonstrate that morphological features can be used to link cell types across experimental modalities, enabling further comparison of connectivity to gene expression and electrophysiology. We observe unique connectivity rules for predicted Sst cell types.

『摘要』 神经回路的功能由构成回路的细胞类型及其之间的连接共同决定。以往,神经细胞类型的定义依据是形态学、电生理学、转录组表达、连接性或这些方式的组合。Patch-seq技术能够对单个细胞的形态学、电生理学和转录组特性进行表征。综合这些特性,我们在小鼠视觉皮层中定义了28种抑制性、形态-电生理-转录组(morpho-electric-transcriptomic,MET)细胞类型,其中不包括突触连接性。相反,大规模电子显微镜(electron microscopy,EM)技术能够实现神经元局部突触连接性的形态学重建和近乎完整的描述,但不包括转录组或电生理信息。在本文中,我们利用Patch-seq的形态学信息,在大规模EM数据集中预测了转录组定义的抑制性神经元亚类和/或MET类型。我们进一步分析了Martinotti细胞(一种生长抑素(somatostatin,Sst)阳性形态学细胞类型),并成功将其分类为具有不同轴突髓鞘化和突触输出连接模式的Sst MET类型。我们证明,形态学特征可用于连接不同实验方法中的细胞类型,从而能够对连接性与基因表达和电生理学进行更深入的比较。我们观察到了预测Sst细胞类型独特的连接规则。
『总结』 本研究结合Patch-seq和大规模EM技术,定义了小鼠视觉皮层中的抑制性神经元MET类型,并证明了形态学特征可用于跨实验方法连接细胞类型,揭示了Sst细胞类型独特的连接规则。
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『Abstract』Understanding the relationship between circuit connectivity and function is crucial for uncovering how the brain computes. In mouse primary visual cortex, excitatory neurons with similar response properties are more likely to be synaptically connected ; however, broader connectivity rules remain unknown. Here we leverage the millimetre-scale MICrONS dataset to analyse synaptic connectivity and functional properties of neurons across cortical layers and areas. Our results reveal that neurons with similar response properties are preferentially connected within and across layers and areas—including feedback connections—supporting the universality of ‘like-to-like’ connectivity across the visual hierarchy. Using a validated digital twin model, we separated neuronal tuning into feature (what neurons respond to) and spatial (receptive field location) components. We found that only the feature component predicts fine-scale synaptic connections beyond what could be explained by the proximity of axons and dendrites. We also discovered a higher-order rule whereby postsynaptic neuron cohorts downstream of presynaptic cells show greater functional similarity than predicted by a pairwise like-to-like rule. Recurrent neural networks trained on a simple classification task develop connectivity patterns that mirror both pairwise and higher-order rules, with magnitudes similar to those in MICrONS data. Ablation studies in these recurrent neural networks reveal that disrupting like-to-like connections impairs performance more than disrupting random connections. These findings suggest that these connectivity principles may have a functional role in sensory processing and learning, highlighting shared principles between biological and artificial systems.

『摘要』 理解电路连接与功能之间的关系对于揭示大脑的计算机制至关重要。在小鼠初级视觉皮层中,具有相似反应特性的兴奋性神经元更有可能形成突触连接;然而,更广泛的连接规则尚不清楚。本研究利用毫米级的MICrONS数据集来分析跨皮层层和区域的神经元的突触连接和功能特性。研究结果表明,具有相似反应特性的神经元在层内、层间和区域间(包括反馈连接)优先连接,这支持了“相似连接”在视觉层级中的普遍性。我们使用经过验证的数字孪生模型,将神经元的调谐分为特征(神经元对什么作出反应)和空间(感受野位置)两部分。我们发现,只有特征成分能预测超出轴突和树突邻近性所能解释的精细突触连接。我们还发现了一个更高级别的规则,即突触前细胞下游的突触后神经元群体表现出比成对相似连接规则所预测的更高的功能相似性。在简单的分类任务上训练的循环神经网络形成了反映成对和更高级别规则的连接模式,其数量级与MICrONS数据中的相似。对这些循环神经网络进行消融研究表明,破坏相似连接对性能的损害比破坏随机连接更大。这些发现表明,这些连接原则可能在感觉处理和学习中发挥功能性作用,并突出了生物系统与人工系统之间的共同原则。
『总结』 研究发现小鼠视觉皮层中相似神经元优先连接,且这种“相似连接”具有普遍性,对感觉处理和学习至关重要,循环神经网络也表现出类似的连接模式。
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『Abstract』Integrated photonics, particularly silicon photonics, have emerged as cutting-edge technology driven by promising applications such as short-reach communications, autonomous driving, biosensing and photonic computing . As advances in AI lead to growing computing demands, photonic computing has gained considerable attention as an appealing candidate. Nonetheless, there are substantial technical challenges in the scaling up of integrated photonics systems to realize these advantages, such as ensuring consistent performance gains in upscaled integrated device clusters, establishing standard designs and verification processes for complex circuits, as well as packaging large-scale systems. These obstacles arise primarily because of the relative immaturity of integrated photonics manufacturing and the scarcity of advanced packaging solutions involving photonics. Here we report a large-scale integrated photonic accelerator comprising more than 16,000 photonic components. The accelerator is designed to deliver standard linear matrix multiply–accumulate (MAC) functions, enabling computing with high speed up to 1 GHz frequency and low latency as small as 3 ns per cycle. Logic, memory and control functions that support photonic matrix MAC operations were designed into a cointegrated electronics chip. To seamlessly integrate the electronics and photonics chips at the commercial scale, we have made use of an innovative 2.5D hybrid advanced packaging approach. Through the development of this accelerator system, we demonstrate an ultralow computation latency for heuristic solvers of computationally hard Ising problems whose performance greatly relies on the computing latency.

『摘要』 集成光子学,特别是硅光子学,已经成为由短距离通信、自动驾驶、生物传感和光子计算等前景广阔的应用驱动的前沿技术。随着人工智能的发展带来日益增长的计算需求,光子计算作为一种颇具吸引力的候选技术,受到了广泛关注。然而,在扩大集成光子学系统以实现这些优势时,仍面临着重大技术挑战,例如确保扩容后的集成器件集群性能持续提升、为复杂电路建立标准设计和验证流程以及大规模系统的封装等。这些障碍主要是由于集成光子学制造工艺相对不成熟,以及涉及光子学的先进封装解决方案较为稀缺。本文介绍了一种包含16000多个光子组件的大规模集成光子加速器。该加速器旨在实现标准的线性矩阵乘积累加(MAC)功能,能够以高达1吉赫兹(GHz)的频率进行高速计算,每个周期的延迟低至3纳秒(ns)。支持光子矩阵MAC操作的逻辑、存储和控制功能被设计进一个共集成的电子芯片中。为了在商业规模上实现电子和光子芯片的无缝集成,我们采用了一种创新的2.5D混合先进封装方法。通过开发这一加速器系统,我们在求解计算难度较高的伊辛问题的启发式求解器上实现了超低计算延迟,其性能在很大程度上依赖于计算延迟。
『总结』 本研究报道了一种由16000多个光子组件组成的大规模集成光子加速器,采用创新的2.5D混合先进封装技术,实现了高速低延迟计算,展示了在求解复杂问题上的超低延迟性能。
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『Abstract』We are in the era of millimetre-scale electron microscopy volumes collected at nanometre resolution . Dense reconstruction of cellular compartments in these electron microscopy volumes has been enabled by recent advances in machine learning . Automated segmentation methods produce exceptionally accurate reconstructions of cells, but post hoc proofreading is still required to generate large connectomes that are free of merge and split errors. The elaborate 3D meshes of neurons in these volumes contain detailed morphological information at multiple scales, from the diameter, shape and branching patterns of axons and dendrites, down to the fine-scale structure of dendritic spines. However, extracting these features can require substantial effort to piece together existing tools into custom workflows. Here, building on existing open source software for mesh manipulation, we present Neural Decomposition (NEURD), a software package that decomposes meshed neurons into compact and extensively annotated graph representations. With these feature-rich graphs, we automate a variety of tasks such as state-of-the-art automated proofreading of merge errors, cell classification, spine detection, axonal-dendritic proximities and other annotations. These features enable many downstream analyses of neural morphology and connectivity, making these massive and complex datasets more accessible to neuroscience researchers.

『摘要』 我们正处于以纳米分辨率收集毫米级电子显微镜图像数据的时代。机器学习的最新进展已经能够实现对这些电子显微镜图像数据中细胞区域的高密度重建。自动化的分割方法可以生成异常精确的细胞重建图像,但要生成没有合并和分裂错误的大型连接组,仍需要进行事后校对。这些图像数据中神经元的精细三维网格包含了多尺度上的详细形态信息,从轴突和树突的直径、形状和分支模式,到树突棘的精细结构一应俱全。然而,要提取这些特征,需要将现有工具整合到定制工作流程中,这一过程需要付出大量努力。在此,我们在现有的网格处理开源软件的基础上,推出了神经元分解(Neural Decomposition,NEURD)软件包,该软件包可以将网格化的神经元分解成紧凑且注释丰富的图形表示。借助这些功能丰富的图形,我们实现了多种任务的自动化,如最先进的合并错误自动化校对、细胞分类、树突棘检测、轴突-树突邻近性检测和其他注释。这些功能能够对神经元的形态和连接性进行许多下游分析,使神经科学研究者更容易获取这些海量而复杂的数据集。
『总结』 我们开发了神经元分解软件包NEURD,能够将电子显微镜图像数据中的网格化神经元转化成图形表示,自动化多种神经形态学分析任务,提高数据集的易用性。
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『Abstract』Magnonic systems provide a fertile playground for bosonic topology , for example, Dirac and Weyl magnons, leading to a variety of exotic phenomena such as charge-free topologically protected boundary modes , the magnon thermal Hall effect and the magnon spin Nernst effect . However, their understanding has been hindered by the absence of fundamental symmetry descriptions of magnetic geometries and spin Hamiltonians primarily governed by isotropic Heisenberg interactions. The ensuing magnon dispersions enable gapless magnon band nodes that go beyond the scenario of representation theory of the magnetic space groups , thus referred to as unconventional magnons. Here we developed spin space group theory to elucidate collinear magnetic configurations, classifying the 1,421 collinear spin space groups into 4 types, constructing their band representations and providing a comprehensive tabulation of unconventional magnons, such as duodecuple points, octuple nodal lines and charge-4 octuple points. On the basis of the MAGNDATA database , we identified 498 collinear magnets with unconventional magnons, among which more than 200 magnon band structures were obtained by using first-principles calculations and linear spin wave theory. In addition, we evaluated the influence of the spin–orbit-coupling-induced exchange interaction in these magnets and found that more than 80 per cent are predominantly governed by the Heisenberg interactions, indicating that the spin space group serves as an ideal framework for describing magnon band nodes in most 3 d , 4 d and half-filled 4 f collinear magnets.

『摘要』 磁振子系统为玻色子拓扑提供了一个丰富的研究领域,例如狄拉克磁振子和外尔磁振子,导致了多种奇异现象,如无电荷拓扑保护的边界模式、磁振子热霍尔效应和磁振子自旋能斯特效应。然而,由于缺乏对主要由各向同性海森堡相互作用支配的磁性几何结构和自旋哈密顿量的基本对称性描述,人们对它们的理解一直受到阻碍。由此产生的磁振子色散使得无带隙磁振子能带节点超出了磁性空间群表示理论的范畴,因此被称为非常规磁振子。在此,我们发展了自旋空间群理论来阐明共线磁性构型,将1421个共线自旋空间群分为4种类型,构建了它们的能带表示,并非常规磁振子(如十二重点、八重节点线和四电荷八重点)提供了全面的表格。基于MAGNDATA数据库,我们确定了498种具有非常规磁振子的共线磁体,其中通过第一性原理计算和线性自旋波理论获得了200多种磁振子能带结构。此外,我们还评估了这些磁体中自旋-轨道耦合诱导的交换相互作用的影响,并发现超过80%的磁体主要受海森堡相互作用支配,这表明自旋空间群是描述大多数3d、4d和半满4f共线磁体中磁振子能带节点的理想框架。
『总结』 本研究发展了自旋空间群理论,对共线磁性构型进行了分类,并发现了498种具有非常规磁振子的共线磁体,其中大多数主要受海森堡相互作用支配。
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『Abstract』The coronavirus membrane protein (M) is the main organizer of coronavirus assembly . Here, we report on an M-targeting molecule, CIM-834, that blocks the assembly of SARS-CoV-2. CIM-834 was obtained through high-throughput phenotypic antiviral screening followed by medicinal-chemistry efforts and target elucidation. CIM-834 inhibits the replication of SARS-CoV-2 (including a broad panel of variants) and SARS-CoV. In SCID mice and Syrian hamsters intranasally infected with SARS-CoV-2, oral treatment reduced lung viral titres to nearly undetectable levels, even (as shown in mice) when treatment was delayed until 24 h before the end point. Treatment of infected hamsters prevented transmission to untreated sentinels. Transmission electron microscopy studies show that virion assembly is completely absent in cells treated with CIM-834. Single-particle cryo-electron microscopy reveals that CIM-834 binds and stabilizes the M protein in its short form, thereby preventing the conformational switch to the long form, which is required for successful particle assembly. In conclusion, we have discovered a new druggable target in the replication cycle of coronaviruses and a small molecule that potently inhibits it.

『摘要』 冠状病毒膜蛋白(M)是冠状病毒组装的主要组织者。本研究报道了一种M靶向分子CIM-834,可阻断SARS-CoV-2的组装。CIM-834是通过高通量表型抗病毒筛选,再结合药物化学研究和靶标阐明而获得的。CIM-834可抑制SARS-CoV-2(包括多种变异株)和SARS-CoV的复制。在鼻内感染SARS-CoV-2的严重联合免疫缺陷(SCID)小鼠和叙利亚金黄地鼠中,口服该药治疗可将肺部病毒滴度降低至几乎检测不到的水平,甚至在(小鼠实验显示的)治疗推迟到终点前24小时才开始的情况下仍然有效。对感染的地鼠进行治疗可防止病毒传播给未接受治疗的哨兵地鼠。透射电子显微镜研究表明,经CIM-834处理的细胞完全缺乏病毒颗粒组装。单颗粒冷冻电子显微镜显示,CIM-834与M蛋白的短形式结合并使其稳定,从而阻止了向长形式的构象转变,而长形式是病毒颗粒成功组装所必需的。总之,本研究在冠状病毒的复制周期中发现了一个新的可药物作用靶点,以及一种对其具有强效抑制作用的小分子。
『总结』 本研究发现了一种靶向冠状病毒膜蛋白的小分子CIM-834,能有效阻断SARS-CoV-2的组装和复制。
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『Abstract』Understanding the brain requires understanding neurons’ functional responses to the circuit architecture shaping them. Here we introduce the MICrONS functional connectomics dataset with dense calcium imaging of around 75,000 neurons in primary visual cortex (VISp) and higher visual areas (VISrl, VISal and VISlm) in an awake mouse that is viewing natural and synthetic stimuli. These data are co-registered with an electron microscopy reconstruction containing more than 200,000 cells and 0.5 billion synapses. Proofreading of a subset of neurons yielded reconstructions that include complete dendritic trees as well the local and inter-areal axonal projections that map up to thousands of cell-to-cell connections per neuron. Released as an open-access resource, this dataset includes the tools for data retrieval and analysis . Accompanying studies describe its use for comprehensive characterization of cell types , a synaptic level connectivity diagram of a cortical column , and uncovering cell-type-specific inhibitory connectivity that can be linked to gene expression data . Functionally, we identify new computational principles of how information is integrated across visual space , characterize novel types of neuronal invariances and bring structure and function together to uncover a general principle for connectivity between excitatory neurons within and across areas .

『摘要』 理解大脑需要了解神经元对塑造它们的电路架构的功能反应。在这里,我们介绍了MICrONS功能连接组数据集,该数据集包含了一只清醒小鼠在观察自然和合成刺激时,其初级视觉皮层(VISp)和高级视觉区域(VISrl、VISal和VISlm)中约75000个神经元的密集钙成像。这些数据与包含20多万个细胞和5亿个突触的电子显微镜重建图像进行了联合配准。对部分神经元进行校对后,得到了包括完整的树突树以及局部和区域间轴突投射的重建图像,这些投射可以映射出每个神经元多达数千个的细胞间连接。该数据集作为开放获取资源发布,包含了数据检索和分析工具。相关研究描述了该数据集在细胞类型全面特征分析、皮层柱突触水平连接图以及揭示可与基因表达数据相关联的细胞类型特异性抑制性连接方面的应用。在功能方面,我们发现了信息如何在视觉空间中整合的新计算原理,描述了新型神经元不变性特征,并将结构与功能相结合,揭示了区域内和区域间兴奋性神经元之间连接的一般原理。
『总结』 MICrONS功能连接组数据集提供了小鼠视觉皮层神经元的密集钙成像与电子显微镜重建图像,助力研究细胞类型、突触连接及神经元信息整合机制。
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『Abstract』Macrophages specialize in phagocytosis, a cellular process that eliminates extracellular matter, including microorganisms, through internalization and degradation . Despite the critical role of phagocytosis during bacterial infection, the fate of phagocytosed microbial cargo and its impact on the host cell are poorly understood. In this study, we show that ingested bacteria constitute an alternative nutrient source that skews immunometabolic host responses. By tracing stable isotope-labelled bacteria, we found that phagolysosomal degradation of bacteria provides carbon atoms and amino acids that are recycled into various metabolic pathways, including glutathione and itaconate biosynthesis, and satisfies the bioenergetic needs of macrophages. Metabolic recycling of microbially derived nutrients is regulated by the nutrient-sensing mechanistic target of rapamycin complex C1 and is intricately tied to microbial viability. Dead bacteria, as opposed to live bacteria, are enriched in cyclic adenosine monophosphate, sustain the cellular adenosine monophosphate pool and subsequently activate adenosine monophosphate protein kinase to inhibit the mechanistic target of rapamycin complex C1. Consequently, killed bacteria strongly fuel metabolic recycling and support macrophage survival but elicit decreased reactive oxygen species production and reduced interleukin-1β secretion compared to viable bacteria. These results provide a new insight into the fate of engulfed microorganisms and highlight a microbial viability-associated metabolite that triggers host metabolic and immune responses. Our findings hold promise for shaping immunometabolic intervention for various immune-related pathologies.

『摘要』 巨噬细胞专门进行吞噬作用,这是一种通过内化和降解来消除包括微生物在内的细胞外物质的细胞过程。尽管吞噬作用在细菌感染过程中起着关键作用,但关于吞噬的微生物货物的命运及其对宿主细胞的影响却知之甚少。本研究表明,摄入的细菌构成了一种替代性营养来源,可改变免疫代谢宿主反应。通过追踪稳定同位素标记的细菌,我们发现噬菌溶酶体对细菌的降解提供了碳原子和氨基酸,这些物质被回收到各种代谢途径中,包括谷胱甘肽和衣康酸的生物合成,并满足了巨噬细胞的生物能量需求。微生物来源的营养素的代谢回收受营养物质感应机制靶点雷帕霉素复合物C1的调控,并与微生物活力密切相关。与活菌相比,死菌中富含环磷酸腺苷,能够维持细胞内的磷酸腺苷池,进而激活磷酸腺苷活化蛋白激酶以抑制机制靶点雷帕霉素复合物C1。因此,与活菌相比,被杀死的细菌强烈促进代谢回收并支持巨噬细胞的存活,但会引起活性氧物种产生减少和白细胞介素-1β分泌减少。这些研究结果为理解被吞噬微生物的命运提供了新的见解,并强调了一种与微生物活力相关的代谢产物,可触发宿主代谢和免疫反应。我们的发现有望为各种免疫相关病理的免疫代谢干预提供新思路。
『总结』 本研究发现摄入的细菌是巨噬细胞的一种替代性营养来源,其代谢回收受雷帕霉素复合物C1调控,且与微生物活力密切相关,为免疫代谢干预提供了新视角。
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『Abstract』Mammalian cortex features a vast diversity of neuronal cell types, each with characteristic anatomical, molecular and functional properties . Synaptic connectivity shapes how each cell type participates in the cortical circuit, but mapping connectivity rules at the resolution of distinct cell types remains difficult. Here we used millimetre-scale volumetric electron microscopy to investigate the connectivity of all inhibitory neurons across a densely segmented neuronal population of 1,352 cells spanning all layers of mouse visual cortex, producing a wiring diagram of inhibition with more than 70,000 synapses. Inspired by classical neuroanatomy, we classified inhibitory neurons based on targeting of dendritic compartments and developed an excitatory neuron classification based on dendritic reconstructions with whole-cell maps of synaptic input. Single-cell connectivity showed a class of disinhibitory specialist that targets basket cells. Analysis of inhibitory connectivity onto excitatory neurons found widespread specificity, with many interneurons exhibiting differential targeting of spatially intermingled subpopulations. Inhibitory targeting was organized into ‘motif groups’, diverse sets of cells that collectively target both perisomatic and dendritic compartments of the same excitatory targets. Collectively, our analysis identified new organizing principles for cortical inhibition and will serve as a foundation for linking contemporary multimodal neuronal atlases with the cortical wiring diagram.

『摘要』 哺乳动物的皮层拥有种类繁多的神经元细胞,每种细胞都具有独特的解剖、分子和功能特性。突触连接决定了每种细胞类型在皮层回路中的参与方式,但要在特定细胞类型的分辨率下绘制连接规则仍然很困难。本研究采用毫米级体积电子显微镜技术,研究了小鼠视觉皮层所有层级中1352个密集分割神经元群体中所有抑制性神经元的连接情况,绘制了包含7万多个突触的抑制性连接图谱。受经典神经解剖学启发,本研究根据树突靶点的定位对抑制性神经元进行了分类,并根据树突重建和全细胞突触输入图谱对兴奋性神经元进行了分类。单细胞连接性显示了一类专门靶向篮状细胞的去抑制性专家细胞。对兴奋性神经元上的抑制性连接的分析发现了广泛的特异性,许多中间神经元对空间上交织在一起的亚群表现出不同的靶向性。抑制性靶向被组织成“模体群”,即一组多样化的细胞,它们共同靶向同一兴奋性靶标的胞体周围和树突区域。总体而言,本研究发现了皮层抑制性连接的新组织原理,并将为当代多模态神经元图谱与皮层连接图谱的联系奠定基础。
『总结』 本研究利用毫米级体积电子显微镜揭示了小鼠视觉皮层中抑制性神经元的连接图谱,发现了新的皮层抑制性连接组织原理,为神经科学研究提供了重要基础。
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『Abstract』Although Earth, together with other terrestrial planets, must have had an early-formed protocrust, the chemical composition of this crust has received little attention. The protocrust was extracted from an extensive magma ocean formed by accretion and melting of asteroidal bodies . Both experimental and chronological data suggest that the silicate melt ascending from this magma ocean formed in equilibrium with, or after, metal was extracted to form Earth’s core. Here we show that a protocrust formed under these conditions would have had incompatible (with respect to silicate minerals) trace-element characteristics remarkably similar to those of the current average continental crust. This has major implications for subsequent planetary evolution. Many geochemical arguments for when and how plate tectonics began implicitly assume that subduction is required to produce the continental trace-element signature. These arguments are severely compromised if this signature was already a feature of the Hadean protocrust.

『摘要』 尽管地球和其他类地行星在早期必定已经形成了原始地壳,但这一地壳的化学成分却鲜少有人关注。原始地壳是从由小行星体吸积和熔化形成的广阔岩浆海洋中提取出来的。实验数据和年代学数据均表明,从这一岩浆海洋中上升的硅酸盐熔体与金属提取形成地球地核的过程同时或在其后形成,并处于平衡状态。本研究表明,在这种条件下形成的原始地壳将具有与当前平均大陆地壳极为相似的不相容(相对于硅酸盐矿物)微量元素特征。这对后续的行星演化具有重大意义。许多关于板块构造何时以及如何开始的地球化学观点都隐含地假设,俯冲作用是产生大陆微量元素特征的必要条件。但如果这种特征已经是冥古宙原始地壳的一个特征,那么这些观点将受到严重质疑。
『总结』 研究发现地球早期形成的原始地壳具有与当前大陆地壳相似的微量元素特征,这对板块构造起源的传统观点提出了挑战。
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『Abstract』Acoustic oscillations in stars are sensitive to stellar interiors . Frequency differences between overtone modes—large separations—probe stellar density , whereas differences between low-degree modes—small separations—probe the sound-speed gradient in the energy-generating core of main-sequence Sun-like stars , and hence their ages. At later phases of stellar evolution, characterized by inert cores, small separations are believed to lose much of their power to probe deep interiors and become proportional to large separations . Here we present evidence of a rapidly evolving convective zone as stars evolve from the subgiant phase into red giants. By measuring acoustic oscillations in 27 stars from the open cluster M67, we observe deviations of proportionality between small and large separations, which are caused by the influence of the bottom of the convective envelope. These deviations become apparent as the convective envelope penetrates deep into the star during subgiant and red giant evolutions, eventually entering an ultradeep regime that leads to the red-giant-branch luminosity bump. The tight sequence of cluster stars, free of large spreads in ages and fundamental properties, is essential for revealing the connection between the observed small separations and the chemical discontinuities occurring at the bottom of the convective envelope. We use this sequence to show that combining large and small separations can improve estimations of the masses and ages of field stars well after the main sequence.

『摘要』 恒星中的声波振荡对恒星内部环境极为敏感。泛音模(即大间距)之间的频率差异可以探测恒星密度,而低度模(即小间距)之间的差异则可以探测类似太阳的主序星能量产生核心中的声速梯度,从而推断它们的年龄。在恒星演化的后期阶段,其特点为具有惰性核,小间距被认为失去了探测恒星深层内部的大部分能力,而是与大间距成比例。在此,我们提出了恒星从亚巨星阶段演化为红巨星过程中对流区快速演化的证据。通过对疏散星团M67中27颗恒星的声波振荡进行测量,我们观察到了小间距与大间距之间比例关系的偏差,这种偏差是由对流包层底部的影响造成的。随着亚巨星和红巨星演化过程中对流包层深入恒星内部,这种偏差变得明显,最终进入一个导致红巨星支光度驼峰的超深范围。星团恒星序列紧密,年龄和基本性质差异不大,这对于揭示观察到的小间距与对流包层底部发生的化学不连续性之间的联系至关重要。我们利用这一序列表明,即使在主序后很长时间,结合大间距和小间距也可以改进对场星质量和年龄的估计。
『总结』 研究通过测量M67星团恒星的声波振荡,发现了恒星演化过程中对流区快速变化的证据,并表明结合大间距和小间距可改进对恒星质量和年龄的估计。
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『Abstract』The membrane (M) protein of betacoronaviruses is well conserved and has a key role in viral assembly . Here we describe the identification of JNJ-9676, a small-molecule inhibitor targeting the coronavirus M protein. JNJ-9676 demonstrates in vitro nanomolar antiviral activity against SARS-CoV-2, SARS-CoV and sarbecovirus strains from bat and pangolin zoonotic origin. Using cryogenic electron microscopy (cryo-EM), we determined a binding pocket of JNJ-9676 formed by the transmembrane domains of the M protein dimer. Compound binding stabilized the M protein dimer in an altered conformational state between its long and short forms, preventing the release of infectious virus. In a pre-exposure Syrian golden hamster model, JNJ-9676 (25 mg per kg twice per day) showed excellent efficacy, illustrated by a significant reduction in viral load and infectious virus in the lung by 3.5 and 4 log 10 -transformed RNA copies and 50% tissue culture infective dose (TCID 50 ) per mg lung, respectively. Histopathology scores at this dose were reduced to the baseline. In a post-exposure hamster model, JNJ-9676 was efficacious at 75 mg per kg twice per day even when added at 48 h after infection, when peak viral loads were observed. The M protein is an attractive antiviral target to block coronavirus replication, and JNJ-9676 represents an interesting chemical series towards identifying clinical candidates addressing the current and future coronavirus pandemics.

『摘要』 β冠状病毒(betacoronavirus)的膜(M)蛋白高度保守,在病毒组装中发挥关键作用。本研究描述了JNJ-9676的鉴定结果,JNJ-9676是一种靶向冠状病毒M蛋白的小分子抑制剂。JNJ-9676在体外对SARS-CoV-2、SARS-CoV以及来自蝙蝠和穿山甲的动物源性sarbecovirus毒株表现出纳摩尔级的抗病毒活性。我们利用冷冻电子显微镜(cryo-EM)确定了JNJ-9676的结合口袋,该口袋由M蛋白二聚体的跨膜结构域形成。化合物结合使M蛋白二聚体在其长短构象之间稳定于一种改变的构象状态,从而阻止感染性病毒的释放。在叙利亚金黄地鼠暴露前模型中,JNJ-9676(25 mg/kg,每日两次)表现出优异的疗效,表现为肺中的病毒载量和感染性病毒分别显著降低3.5个和4个log10转换的RNA拷贝数,以及每毫克肺组织50%组织培养感染剂量(TCID50)。在此剂量下,组织病理学评分降低至基线水平。在地鼠暴露后模型中,即使在感染后48小时(观察到病毒载量峰值时)给药,JNJ-9676(75 mg/kg,每日两次)仍然有效。M蛋白是阻断冠状病毒复制的一个有吸引力的抗病毒靶点,而JNJ-9676代表了一个有趣的化学系列,可用于鉴定应对当前和未来冠状病毒大流行的临床候选药物。
『总结』 研究发现JNJ-9676是一种靶向冠状病毒M蛋白的小分子抑制剂,具有显著的体外和体内抗病毒活性,为抗击冠状病毒提供了新策略。
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『Abstract』Limited strategies exist for chemical recycling of commodity diene polymers, like those found in tyres . Here we apply C–H amination and backbone rearrangement of polymers to deconstruct these materials into precursors for epoxy resins. Specifically, we develop a sulfur diimide reagent that enables up to about 35% allylic amination of diene polymers and rubber. Then, we apply the cationic 2-aza-Cope rearrangement to deconstruct aminated diene polymers. In a model system, we see molecular weight reduction from 58,100 to approximately 400 g mol , and aminated post-consumer rubber is deconstructed over 6 hours into soluble amine-functionalized polymers, which can be utilized to prepare epoxy thermosets with similar stiffnesses to commercial bisphenol A-derived resins . Altogether, this work demonstrates the power of C–H amination and backbone rearrangement to enable chemical recycling of post-consumer materials.

『摘要』 通用二烯聚合物(如轮胎中的聚合物)的化学回收策略有限。本研究采用C–H胺化和聚合物骨架重排的方法将这些材料分解成环氧树脂的前体。具体而言,本研究开发了一种硫二亚胺试剂,可使二烯聚合物和橡胶实现高达35%左右的烯丙基胺化。然后,利用阳离子2-氮杂-科普重排反应对胺化二烯聚合物进行解构。在一个模型系统中,本研究观察到分子量从58100降低到了约400 g/mol,并且在6小时内将胺化后的废旧橡胶分解成可溶的胺基功能化聚合物,该聚合物可用于制备与商业双酚A衍生树脂刚度相似的环氧热固性树脂。总体而言,本研究证明了C–H胺化和骨架重排在实现废旧材料化学回收方面的强大作用。
『总结』 本研究通过C–H胺化和聚合物骨架重排实现了通用二烯聚合物的化学回收,为废旧橡胶等材料提供了新的回收利用途径。
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『Abstract』Cortical networks for the production of spoken language in humans are organized by phonetic features , such as articulatory parameters and vocal pitch . Previous research has failed to find an equivalent forebrain representation in other species . To investigate whether this functional organization is unique to humans, here we performed population recordings in the vocal production circuitry of the budgerigar ( Melopsittacus undulatus ), a small parrot that can generate flexible vocal output , including mimicked speech sounds . Using high-density silicon probes , we measured the song-related activity of a forebrain region, the central nucleus of the anterior arcopallium (AAC), which directly projects to brainstem phonatory motor neurons . We found that AAC neurons form a functional vocal motor map that reflects the spectral properties of ongoing vocalizations. We did not observe this organizing principle in the corresponding forebrain circuitry of the zebra finch, a songbird capable of more limited vocal learning . We further demonstrated that the AAC represents the production of distinct vocal features (for example, harmonic structure and broadband energy). Furthermore, we discovered an orderly representation of vocal pitch at the population level, with single neurons systematically selective for different frequency values. Taken together, we have uncovered a functional representation in a vertebrate brain that displays unprecedented commonalities with speech-related motor cortices in humans. This work therefore establishes the parrot as an important animal model for investigating speech motor control and for developing therapeutic solutions for addressing a range of communication disorders .

『摘要』 人类的语言产生皮层网络根据音韵特征(如发音参数和音调)进行组织。先前的研究未能在其他物种中发现等效的前脑表征。为研究这种功能组织是否为人类独有,我们对能够发出灵活叫声(包括模仿语音)的小型鹦鹉——虎皮鹦鹉(Melopsittacus undulatus)的发声机制电路进行了群体记录。我们使用高密度硅探针测量了前脑区域前弧状核中央核(AAC)中与歌声相关的活动,该区域直接向脑干发声运动神经元投射。研究发现,AAC神经元形成了一个功能性发声运动图谱,反映了正在进行的发声的频谱特性。我们在发声学习能力更有限的鸣禽——斑马雀的前脑相应回路中未观察到这一组织原理。我们进一步证明,AAC表征不同发声特征(如和声结构和宽频能量)的产生。此外,我们还发现了群体水平上音调的有序表征,单个神经元对不同频率值具有系统性选择性。综上,我们在脊椎动物大脑中发现了一种功能表征,与人类与语言相关的运动皮层具有前所未有的相似性。因此,这项研究确立了鹦鹉作为研究语言运动控制和开发治疗一系列交流障碍方法的重要动物模型。
『总结』 研究发现虎皮鹦鹉的前脑区域AAC中存在与人类语言运动皮层相似的功能性发声运动表征,确立了鹦鹉作为研究语言控制和交流障碍治疗的重要模型。
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『Abstract』Humans emerged across Africa shortly before 300 thousand years ago (ka) . Although this pan-African evolutionary process implicates diverse environments in the human story, the role of tropical forests remains poorly understood. Here we report a clear association between late Middle Pleistocene material culture and a wet tropical forest in southern Cote d’Ivoire, a region of present-day rainforest. Twinned optically stimulated luminescence and electron spin resonance dating methods constrain the onset of human occupations at Bete I to around 150 ka, linking them with Homo sapiens . Plant wax biomarker, stable isotope, phytolith and pollen analyses of associated sediments all point to a wet forest environment. The results represent the oldest yet known clear association between humans and this habitat type. The secure attribution of stone tool assemblages with the wet forest environment demonstrates that Africa’s forests were not a major ecological barrier for H. sapiens as early as around 150 ka.

『摘要』 人类在大约 30 万年前(ka) 不久前在非洲各地出现。虽然这一全非洲范围的进化过程暗示了人类历史中存在不同的环境,但热带森林的作用仍鲜为人知。在此,我们报告了中更新世晚期物质文化与当今热带雨林地区的科特迪瓦南部的潮湿热带雨林之间存在的明确关联。采用光释光与电子自旋共振两种测年方法,将贝特I遗址的人类活动起始时间确定为大约 15 万年前,并将其与智人联系起来。对相关沉积物中的植物蜡生物标志物、稳定同位素、植硅体和花粉的分析均表明,当时存在一个潮湿的森林环境。这一结果代表了迄今为止已知的人类与这种栖息地类型之间最古老且最明确的关联。将石器组合明确地归因于潮湿森林环境表明,早在大约 15 万年前,非洲的森林对智人来说就不是主要的生态障碍。
『总结』 研究发现人类早在 15 万年前就开始在非洲潮湿热带雨林中活动,这表明该森林环境并非智人扩张的生态障碍。
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『Abstract』The tetraploid genome and clonal propagation of the cultivated potato ( Solanum tuberosum L.) dictate a slow, non-accumulative breeding mode of the most important tuber crop. Transitioning potato breeding to a seed-propagated hybrid system based on diploid inbred lines has the potential to greatly accelerate its improvement . Crucially, the development of inbred lines is impeded by manifold deleterious variants; explaining their nature and finding ways to eliminate them is the current focus of hybrid potato research . However, most published diploid potato genomes are unphased, concealing crucial information on haplotype diversity and heterozygosity . Here we develop a phased potato pangenome graph of 60 haplotypes from cultivated diploids and the ancestral wild species, and find evidence for the prevalence of transposable elements in generating structural variants. Compared with the linear reference, the graph pangenome represents a broader diversity (3,076 Mb versus 742 Mb). Notably, we observe enhanced heterozygosity in cultivated diploids compared with wild ones (14.0% versus 9.5%), indicating extensive hybridization during potato domestication. Using conservative criteria, we identify 19,625 putatively deleterious structural variants (dSVs) and reveal a biased accumulation of deleterious single nucleotide polymorphisms (dSNPs) around dSVs in coupling phase. Based on the graph pangenome, we computationally design ideal potato haplotypes with minimal dSNPs and dSVs. These advances provide critical insights into the genomic basis of clonal propagation and will guide breeders to develop a suite of promising inbred lines.

『摘要』 马铃薯(Solanum tuberosum L.)的四倍体基因组和无性繁殖方式决定了这种最重要的块茎作物具有缓慢且非累积的育种模式。将马铃薯育种转变为基于二倍体自交系的种子繁殖杂交体系,有可能极大加速其改良进程。关键在于,自交系的开发受到多种有害变异的阻碍;阐明这些变异的性质并找到消除它们的方法是当前杂交马铃薯研究的重点。然而,大多数已发表的二倍体马铃薯基因组都是未分型的,隐藏了关于单倍型多样性和杂合性的关键信息。本研究构建了包含来自栽培二倍体和野生祖先物种的60个单倍型的马铃薯泛基因组图谱,并发现了转座子在产生结构变异中的普遍作用。与线性参考基因组相比,图谱泛基因组代表了更广泛的多样性(3076 Mb对比742 Mb)。值得注意的是,相较于野生二倍体(9.5%),栽培二倍体表现出更高的杂合性(14.0%),这表明在马铃薯驯化过程中发生了广泛的杂交。采用保守标准,我们鉴定出19625个潜在有害的结构变异(dSVs),并揭示了在耦联相中,有害单核苷酸多态性(dSNPs)在dSVs周围存在偏向性积累。基于图谱泛基因组,我们通过计算设计了具有最少dSNPs和dSVs的理想马铃薯单倍型。这些进展为无性繁殖的基因组基础提供了关键见解,并将指导育种者开发一系列有前景的自交系。
『总结』 本研究构建了马铃薯的泛基因组图谱,揭示了其基因组多样性和结构变异特征,为开发优良自交系提供了重要依据。
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『Abstract』Over the past decade, photonics research has explored accelerated tensor operations, foundational to artificial intelligence (AI) and deep learning , as a path towards enhanced energy efficiency and performance . The field is centrally motivated by finding alternative technologies to extend computational progress in a post-Moore’s law and Dennard scaling era . Despite these advances, no photonic chip has achieved the precision necessary for practical AI applications, and demonstrations have been limited to simplified benchmark tasks. Here we introduce a photonic AI processor that executes advanced AI models, including ResNet and BERT , along with the Atari deep reinforcement learning algorithm originally demonstrated by DeepMind . This processor achieves near-electronic precision for many workloads, marking a notable entry for photonic computing into competition with established electronic AI accelerators and an essential step towards developing post-transistor computing technologies.

『摘要』 过去十年,光子学研究探索了加速张量运算(人工智能(AI)和深度学习的基础),以此作为提高能效和性能的途径。这一领域的核心动力是寻找替代技术,在摩尔定律和后登纳德缩放时代推动计算进步。尽管取得了这些进展,但尚无光子芯片达到实际应用人工智能所需的精度,且目前演示仅限于简化的基准任务。在此,我们推出了一款光子人工智能处理器,可执行先进的人工智能模型,包括ResNet和BERT,以及最初由DeepMind演示的Atari深度强化学习算法。该处理器在许多工作负载上达到了接近电子芯片的精度,标志着光子计算在与成熟电子人工智能加速器的竞争中迈出了重要一步,也是向后晶体管计算技术开发迈出的关键一步。
『总结』 研究人员开发出一款光子AI处理器,可执行先进AI模型并达到接近电子芯片的精度,为后晶体管计算技术开发迈出了关键一步。
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『Abstract』Existing wearable technologies rely on physical coupling to the body to establish optical , fluidic , thermal and/or mechanical measurement interfaces. Here we present a class of wearable device platforms that instead relies on physical decoupling to define an enclosed chamber immediately adjacent to the skin surface. Streams of vapourized molecular substances that pass out of or into the skin alter the properties of the microclimate defined in this chamber in ways that can be precisely quantified using an integrated collection of wireless sensors. A programmable, bistable valve dynamically controls access to the surrounding environment, thereby creating a transient response that can be quantitatively related to the inward and outward fluxes of the targeted species by analysing the time-dependent readings from the sensors. The systems reported here offer unique capabilities in measuring the flux of water vapour, volatile organic compounds and carbon dioxide from various locations on the body, each with distinct relevance to clinical care and/or exposure to hazardous vapours. Studies of healing processes associated with dermal wounds in models of healthy and diabetic mice and of responses in models using infected wounds reveal characteristic flux variations that provide important insights, particularly in scenarios in which the non-contact operation of the devices avoids potential damage to fragile tissues.

『摘要』 现有的可穿戴技术依赖于与身体的物理耦合来建立光学、流体、热学和/或机械测量界面。本文介绍了一类可穿戴设备平台,该平台依赖于物理去耦合,在紧邻皮肤表面处定义一个封闭腔室。进出皮肤的气态分子物质会改变该腔室内微环境的特性,这些变化可以通过集成的无线传感器组进行精确量化。一个可编程的双稳态阀动态控制腔室与周围环境的接触,从而通过分析传感器的时间相关读数,产生与目标物质向内和向外通量定量相关的瞬态响应。本文报道的系统在测量来自身体不同部位的水蒸气、挥发性有机化合物和二氧化碳的通量方面具有独特的能力,这些通量与临床护理和/或接触有害蒸气密切相关。对健康小鼠和糖尿病小鼠的皮肤伤口愈合过程以及感染伤口模型中的反应的研究揭示了特征性的通量变化,这些变化提供了重要的见解,特别是在设备的非接触操作避免对脆弱组织造成潜在损害的情境中。
『总结』 本文介绍了一类新型可穿戴设备,通过物理去耦合在皮肤表面附近形成封闭腔室,并利用无线传感器精确量化进出皮肤的气态分子通量,为临床护理和监测提供了重要工具。
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『Abstract』The survival of malignant cells within tumours is often seen as depending on ruthless competition for nutrients and other resources . Although competition is certainly critical for tumour evolution and cancer progression, cooperative interactions within tumours are also important, albeit poorly understood . Cooperative populations at all levels of biological organization risk extinction if their population size falls below a critical tipping point . Here we examined whether cooperation among tumour cells may be a potential therapeutic target. We identified a cooperative mechanism that enables tumour cells to proliferate under the amino acid-deprived conditions found in the tumour microenvironment. Disruption of this mechanism drove cultured tumour populations to the critical extinction point and resulted in a marked reduction in tumour growth in vivo. Mechanistically, we show that tumour cells collectively digest extracellular oligopeptides through the secretion of aminopeptidases. The resulting free amino acids benefit both aminopeptidase-secreting cells and neighbouring cells. We identified CNDP2 as the key enzyme that hydrolyses these peptides extracellularly, and loss of this aminopeptidase prevents tumour growth in vitro and in vivo. These data show that cooperative scavenging of nutrients is key to survival in the tumour microenvironment and reveal a targetable cancer vulnerability.

『摘要』 在肿瘤中,恶性细胞的存活通常被视为依赖于对营养物质和其他资源的无情竞争。尽管竞争对于肿瘤进化和癌症进展无疑至关重要,但肿瘤内部的合作也同样重要,只是这一点尚未得到充分了解。在生物组织的各个层面上,合作群体如果其数量低于关键的临界点,都会面临灭绝的风险。本研究探讨了肿瘤细胞之间的合作是否可能成为一个潜在的治疗靶点。我们发现了一种合作机制,使肿瘤细胞能够在肿瘤微环境中氨基酸缺乏的条件下增殖。破坏这种机制会使培养的肿瘤细胞群达到临界灭绝点,并显著抑制体内肿瘤的生长。从机制上讲,我们发现肿瘤细胞通过分泌氨基肽酶来集体消化细胞外寡肽。由此产生的游离氨基酸对分泌氨基肽酶的细胞和邻近细胞都有益。我们确定CNDP2是在细胞外水解这些肽的关键酶,而失去这种氨基肽酶会阻止体内外肿瘤的生长。这些数据表明,合作性获取营养物质是肿瘤微环境中生存的关键,并揭示了一种可靶向的癌症脆弱性。
『总结』 研究表明肿瘤细胞通过合作机制在营养缺乏环境中生存,破坏该机制可抑制肿瘤生长,提示了癌症治疗的新靶点。
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