编译 | 李言
nature, 14 december 2023, volume 624 issue 7991
《自然》2023年12月14日，第624卷，7991期
天文学astronomy
15nh3 in the atmosphere of a cool brown dwarf
一颗低温褐矮星大气中的15nh33
▲ 作者：david barrado, paul mollière et al.
▲ 链接：
https://www.nature.com/articles/s41586-023-06813-y
▲ 摘要：
在此，我们报告了jwst中红外仪器对有效温度为380 k的冷褐矮星大气中14nh3和15nh3同位素异构体的中红外探测结果。
正如预期所想，我们的结果揭示了14n/15n的值与引力坍缩形成类星的过程一致，表明这个比率可以精确测定。因为年轻的恒星和它们的行星通常含有更多的15n同位素，我们预计将在更多低温、宽距离的系外行星上探测到15nh3。
▲ abstract：
here we report on the mid-infrared detection of the 14nh3 and 15nh3 isotopologues in the atmosphere of a cool brown dwarf with an effective temperature of 380?k in a spectrum taken with the mid-infrared instrument (miri) of jwst. as expected, our results reveal a 14n/15n value consistent with star-like formation by gravitational collapse, demonstrating that this ratio can be accurately constrained. because young stars and their planets should be more strongly enriched in the 15n isotope, we expect that 15nh3 will be detectable in several cold, wide-separation exoplanets.
物理学physics
reconfigurable moiré nanolaser arrays with phase synchronization
具有相位同步的可重构莫尔纳米激光器阵列
▲ 作者：hong-yi luan, yun-hao ouyang et al.
▲ 链接：
https://www.nature.com/articles/s41586-023-06789-9
▲ 摘要：
在此，我们提出并展示了基于扭曲光子石墨烯晶格中的光学平带的莫尔纳米激光器阵列，可以实现从单个纳米腔到可重构纳米腔阵列的相干纳米化。我们观察到同步纳米激光阵列在一系列不同的图案上表现出高度的空间和光谱相干性，包括p形、k形和u形，以及汉字“中国”和“中国”。
此外，我们获得了以空间变化的相对相位发射的纳米激光器阵列，使我们能够操纵发射方向。我们的工作为可重构有源器件的开发奠定了基础，这些器件在通信、激光雷达（光探测和测距）、光学计算和成像方面具有应用潜力。
▲ abstract：
here we propose and demonstrate moiré nanolaser arrays based on optical flatbands in twisted photonic graphene lattices, in which coherent nanolasing is realized from a single nanocavity to reconfigurable arrays of nanocavities. we observe synchronized nanolaser arrays exhibiting high spatial and spectral coherence, across a range of distinct patterns, including p, k and u shapes and the chinese characters ‘中’ and ‘国’ (‘china’ in chinese). moreover, we obtain nanolaser arrays that emit with spatially varying relative phases, allowing us to manipulate emission directions. our work lays the foundation for the development of reconfigurable active devices that have potential applications in communication, lidar (light detection and ranging), optical computing and imaging.
材料科学materials science
multiscale stress deconcentration amplifies fatigue resistance of rubber
多尺度应力分散增强了橡胶的抗疲劳性能
▲ 作者：jason steck, junsoo kim et al.
▲ 链接：
https://www.nature.com/articles/s41586-023-06782-2
▲ 摘要：
在此，我们通过多尺度应力分散放大了颗粒增强橡胶的疲劳阈值。我们合成了一种高度纠缠的长聚合物与刚性颗粒紧密结合的橡胶。在裂纹尖端，应力分散在两个长度尺度上：首先通过聚合物，然后通过颗粒。这种橡胶的疲劳阈值约为1000?j?m?2。
由这种橡胶制成的支架和夹具承受高载荷能力，在重复操作中还能抵抗裂纹增长。多尺度应力集中扩展了材料性能的空间，为减少聚合物污染和建造高性能软机械打开了新思路。
▲ abstract：
here we amplify the fatigue threshold of particle-reinforced rubbers by multiscale stress deconcentration. we synthesize a rubber in which highly entangled long polymers strongly adhere with rigid particles. at a crack tip, stress deconcentrates across two length scales: first through polymers and then through particles. this rubber achieves a fatigue threshold of approximately 1,000?j?m?2. mounts and grippers made of this rubber bear high loads and resist crack growth over repeated operation. multiscale stress deconcentration expands the space of materials properties, opening doors to curtailing polymer pollution and building high-performance soft machines.
气候科学climate science
spread in climate policy scenarios unravelled
揭示气候政策情景的扩散
▲ 作者：mark m. dekker, andries f. hof et al.
▲ 链接：
https://www.nature.com/articles/s41586-023-06738-6
▲ 摘要：
对气候政策情景中的扩散全面归因有助于决策者、利益相关者和科学家应对该领域的巨大不确定性。在此，我们使用sobol分解将这种分布归因于底层驱动因素，从而得出每个驱动因素对场景结果的重要性。
正如预期的那样，气候目标解释了温室气体排放、化石燃料总量和地区使用情况、可再生能源总量以及发电中碳捕获和储存总量的大部分分布情况。出乎意料的是，模式差异导致了大多数其他情景结果的变化，例如，在个别可再生能源、碳捕获和储存技术以及需求地区的能源情况，反映了长期发展和可能的缓和策略范围的内在不确定性。
只有少数情景结果——如氢气的使用——是由其他情景假设驱动的，这反映出我们需要更多的情景区分。
▲ abstract：
a comprehensive attribution of the spread in climate policy scenarios helps policymakers, stakeholders and scientists to cope with large uncertainties in this field. here we attribute this spread to the underlying drivers using sobol decomposition, yielding the importance of each driver for scenario outcomes. as expected, the climate target explains most of the spread in greenhouse gas emissions, total and sectoral fossil fuel use, total renewable energy and total carbon capture and storage in electricity generation. unexpectedly, model differences drive variation of most other scenario outcomes, for example, in individual renewable and carbon capture and storage technologies, and energy in demand sectors, reflecting intrinsic uncertainties about long-term developments and the range of possible mitigation strategies. only a few scenario outcomes, such as hydrogen use, are driven by other scenario assumptions, reflecting the need for more scenario differentiation.
生物学biology
the molecular cytoarchitecture of the adult mouse brain
成年小鼠大脑的分子细胞结构
▲ 作者：jonah langlieb, nina s. sachdev et al.
▲ 链接：
https://www.nature.com/articles/s41586-023-06818-7
▲ 摘要：
为了构建每个大脑结构中细胞类型的综合图谱，我们将高通量单核rna测序与slide-seq——一种最近开发的具有近细胞分辨率的空间转录组学方法——在整个小鼠大脑中配对。这些数据集的整合揭示了每个神经解剖结构的细胞类型组成。
我们发现中脑、后脑和下丘脑的细胞类型多样性非常高，大多数集群需要至少三个离散的基因表达标记的组合才能定义。利用这些数据，我们开发了一个以遗传方式访问每种细胞类型的框架，全面描述了神经肽和神经递质信号，阐明了活动调节基因表达的区域特异性，同时确定了神经和精神表型的遗传性富集。
这些数据可以在线使用，在神经科学领域具有找到不同的应用潜力，包括构建新遗传工具和研究大脑疾病中特定细胞类型和电路的优先级。
▲ abstract：
to construct a comprehensive atlas of cell types in each brain structure, we paired high-throughput single-nucleus rna sequencing with slide-seq—a recently developed spatial transcriptomics method with near-cellular resolution—across the entire mouse brain. integration of these datasets revealed the cell type composition of each neuroanatomical structure. cell type diversity was found to be remarkably high in the midbrain, hindbrain and hypothalamus, with most clusters requiring a combination of at least three discrete gene expression markers to uniquely define them. using these data, we developed a framework for genetically accessing each cell type, comprehensively characterized neuropeptide and neurotransmitter signalling, elucidated region-specific specializations in activity-regulated gene expression and ascertained the heritability enrichment of neurological and psychiatric phenotypes. these data, available as an online resource, should find diverse applications across neuroscience, including the construction of new genetic tools and the prioritization of specific cell types and circuits in the study of brain diseases.
a novel antidiuretic hormone governs tumour-induced renal dysfunction
一种可以控制肿瘤引起肾功能障碍的新抗利尿激素
▲ 作者：wenhao xu, gerui li et al.
▲ 链接：
https://www.nature.com/articles/s41586-023-06833-8
▲ 摘要：
在此，通过使用果蝇的保守肿瘤模型，我们将离子运输肽亚型f（itpf）鉴定为一种果蝇抗利尿激素，由yki3sa肠道肿瘤细胞亚群分泌，损害肾功能并导致严重的腹部腹胀和液体积聚。
从机理上，肿瘤来源的itpf靶向马氏管（相当于肾小管的排泄器官）星状细胞中的g蛋白偶联受体tkr99d，激活一氧化氮合酶—gmp信号，抑制液体排泄。我们进一步揭示了哺乳动物神经激肽3受体（nk3r）的抗利尿功能，该受体是苍蝇tkr99d的同源物，通过药物阻断nk3r可有效缓解不同恶性肿瘤小鼠的肾小管功能障碍。
综上，我们的研究结果证明了一种新的抗利尿途径介导跨物种的肿瘤—肾脏交流，为癌症相关肾功能障碍的治疗提供了治疗可能。
▲ abstract：
here, using conserved tumour models in drosophila melanogaster, we characterized isoform f of ion transport peptide (itpf) as a fly antidiuretic hormone that is secreted by a subset of yki3sa gut tumour cells, impairs renal function and causes severe abdomen bloating and fluid accumulation. mechanistically, tumour-derived itpf targets the g-protein-coupled receptor tkr99d in stellate cells of malpighian tubules—an excretory organ that is equivalent to renal tubules—to activate nitric oxide synthase–cgmp signalling and inhibit fluid excretion. we further uncovered antidiuretic functions of mammalian neurokinin 3 receptor (nk3r), the homologue of fly tkr99d, as pharmaceutical blockade of nk3r efficiently alleviates renal tubular dysfunction in mice bearing different malignant tumours. together, our results demonstrate a novel antidiuretic pathway mediating tumour–renal crosstalk across species and offer therapeutic opportunities for the treatment of cancer-associated renal dysfunction.
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