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编译｜李言

Science, 14 JUN 2024, VOL 384, ISSUE 6701

《明升体育app》2024年6月14日，第384卷，6701期

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材料明升体育appMaterials Science

Spectrally engineered textile for radiative cooling against urban heat islands

通过辐射冷却对抗城市热岛效应的光谱工程纺织品

▲ 作者：RONGHUI WU, CHENXI SUI et al.

▲ 链接：

http://www.science.org/doi/10.1126/science.adl0653

▲ 摘要：

我们通过分子设计开发了一种中红外光谱选择性分层织物（SSHF），其发射率在大气透射窗口中占主导地位，最大限度地减少了来自周围环境的净热增益。

由于纳米微混合纤维结构的强烈米氏散射，这一材料具有0.97的高太阳光谱反射率。当材料在白天被垂直放置在模拟室外城市场景中时，它比太阳反射宽带发射器低2.3°C，并且具有出色的可穿戴性能。

▲ Abstract：

We developed a mid-infrared spectrally selective hierarchical fabric (SSHF) with emissivity greatly dominant in the atmospheric transmission window through molecular design, minimizing the net heat gain from the surroundings. The SSHF features a high solar spectrum reflectivity of 0.97 owing to strong Mie scattering from the nano-micro hybrid fibrous structure. The SSHF is 2.3°C cooler than a solar-reflecting broadband emitter when placed vertically in simulated outdoor urban scenarios during the day and also has excellent wearable properties.

海洋明升手机Ocean Chemistry

Biogenic-to-lithogenic handoff of particulate Zn affects the Zn cycle in the Southern Ocean

锌颗粒的生-岩转换影响南大洋中的锌循环

▲ 作者：J. DUAN, R. CLOETE et al.

▲ 链接：

http://www.science.org/doi/10.1126/science.adh8199

▲ 摘要：

锌（Zn）对海洋生物至关重要。浮游植物对锌的积极吸收导致溶解锌的大量消耗，而与颗粒有机物结合的锌通过再矿化作用补充海洋中的溶解锌。然而，我们发现锌颗粒从细胞中与磷酸基结合的锌转变为南大洋水柱中包括生物二氧化硅、粘土、铁、锰和铝的氧化物的顽固无机池。

无机池的丰度随深度增加而增加，是沉积物中唯一保存的。锌颗粒形态的变化影响了锌的生物利用度，并解释了水柱中锌与磷的解耦，以及锌与硅的相关性。这些发现揭示了海洋锌循环的一个新维度，暗示了无机锌颗粒的作用及其对生物生产力的影响。

▲ Abstract：

Zinc (Zn) is vital to marine organisms. Its active uptake by phytoplankton results in a substantial depletion of dissolved Zn, and Zn bound to particulate organic matter replenishes dissolved Zn in the ocean through remineralization. However, we found that particulate Zn changes from Zn bound to phosphoryls in cells to recalcitrant inorganic pools that include biogenic silica, clays, and iron, manganese, and aluminum oxides in the Southern Ocean water column. The abundances of inorganic pools increase with depth and are the only phases preserved in sediments. Changes in the particulate-Zn speciation influence Zn bioavailability and explain the decoupling of Zn and phosphorus and the correlation of Zn and silicon in the water column. These findings reveal a new dimension to the ocean Zn cycle, implicating an underappreciated role of inorganic Zn particles and their impact on biological productivity.

地球明升体育appEarth Science

Human activities shape global patterns of decomposition rates in rivers

人类活动塑造了全球河流分解速率模式

▲ 作者：S. D. TIEGS, K. A. CAPPS et al.

▲ 链接：

http://www.science.org/doi/10.1126/science.adn1262

▲ 摘要：

利用纤维素为基础的分析来反映植物碎屑的主要成分，我们为全球分布的514条河流中的纤维素分解率建立了一个预测模型。分解率预测中存在大量重要的变量，这强调了这一过程在全球范围内的复杂性。

当预测的纤维素分解率与属级凋落叶质量属性相结合时，可以高精度地解释此前研究已得出的凋落叶分解率。我们的全球研究提供了地球上大量未被研究区域的分解率估计，并揭示了人类活动主导的大陆尺度区域中存在的快速分解情况。

▲ Abstract：

Using a cellulose-based assay to reflect the primary constituent of plant detritus, we generated a predictive model (81% variance explained) for cellulose decomposition rates across 514 globally distributed streams. A large number of variables were important for predicting decomposition, highlighting the complexity of this process at the global scale. Predicted cellulose decomposition rates, when combined with genus-level litter quality attributes, explain published leaf litter decomposition rates with high accuracy (70% variance explained). Our global map provides estimates of rates across vast understudied areas of Earth and reveals rapid decomposition across continental-scale areas dominated by human activities.

物理Physics

Probing structural superlubricity of two-dimensional water transport with atomic resolution

用原子分辨率探测二维冰的超润滑现象

▲ 作者：DA WU, ZHENGPU ZHAO et al.

▲ 链接：

http://www.science.org/doi/10.1126/science.ado1544

▲ 摘要：

在这项研究中，我们使用qPlus型扫描探针显微镜直接成像石墨烯和六方氮化硼表面上二维冰的原子结构和输运。由于表面静电的不同，二维冰岛的晶格与石墨烯表面不相称，而与氮化硼表面相称。

石墨烯表面的面积归一化静摩擦随着冰岛面积的增加而减小（约-0.58），表明石墨烯具有超润滑行为。相比之下，氮化硼的摩擦对面积不敏感。分子动力学模拟进一步表明，石墨烯上的冰岛摩擦系数可以降低到小于0.01。

▲ Abstract：

In this work, we directly imaged the atomic structure and transport of two-dimensional water islands on graphene and hexagonal boron nitride surfaces using qPlus-based atomic force microscopy. The lattice of the water island was incommensurate with the graphene surface but commensurate with the boron nitride surface owing to different surface electrostatics. The area-normalized static friction on the graphene diminished as the island area was increased by a power of ~–0.58, suggesting superlubricity behavior. By contrast, the friction on the boron nitride appeared insensitive to the area. Molecular dynamic simulations further showed that the friction coefficient of the water islands on the graphene could reduce to <0.01.

明升手机版Medicine

Integrated platform for multiscale molecular imaging and phenotyping of the human brain

人脑多尺度分子成像和表型的集成平台

▲ 作者：JUHYUK PARK, JI WANG, WEBSTER GUAN et al.

▲ 链接：

http://www.science.org/doi/10.1126/science.adh9979

▲ 摘要：

我们开发了一个平台，可以同时从同一个人的大脑中提取单个细胞的空间、分子、形态和连接信息。该平台包括三个核心元素：用于大规模组织的超精密切片而不失去细胞连通性的振动切片机（MEGAtome），用于人体器官尺度组织的多路多尺度成像的聚合物水凝胶组织处理技术（mELAST），以及用于重建多个脑板之间三维连通性的计算管道（UNSLICE）。我们利用这个平台在多个尺度上分析人类阿尔茨海默病的病理，并展示人类大脑中可扩展的神经连接映射。

▲ Abstract：

We developed a platform that simultaneously extracts spatial, molecular, morphological, and connectivity information of individual cells from the same human brain. The platform includes three core elements: a vibrating microtome for ultraprecision slicing of large-scale tissues without losing cellular connectivity (MEGAtome), a polymer hydrogel–based tissue processing technology for multiplexed multiscale imaging of human organ–scale tissues (mELAST), and a computational pipeline for reconstructing three-dimensional connectivity across multiple brain slabs (UNSLICE). We applied this platform for analyzing human Alzheimer’s disease pathology at multiple scales and demonstrating scalable neural connectivity mapping in the human brain.

Metabolic inflexibility promotes mitochondrial health during liver regeneration

代谢不灵活性在肝脏再生过程中促进线粒体健康

▲ 作者：XUN WANG, CAMERON J. MENEZES et al.

▲ 链接：

http://www.science.org/doi/10.1126/science.adj4301

▲ 摘要：

我们手机版在肝脏再生过程中，由于无法通过线粒体β氧化从外周脂肪酸产生乙酰辅酶a，电子传递链（ETC）功能失调的肝细胞的增殖受到抑制。丙酮酸或醋酸酯产生乙酰辅酶a的可选模式在ETC功能障碍的情况下受到抑制。

这种代谢不灵活性迫使对ETC功能线粒体产生依赖，从丙酮酸中恢复乙酰辅酶a的产生足以使ETC功能失调的肝细胞增殖。我们提出，通过限制ETC功能失调细胞的扩张，可以使得肝细胞内的代谢不灵活性变得有益。

▲ Abstract：

We report that during liver regeneration, proliferation is suppressed in electron transport chain (ETC)–dysfunctional hepatocytes due to an inability to generate acetyl-CoA from peripheral fatty acids through mitochondrial β-oxidation. Alternative modes for acetyl-CoA production from pyruvate or acetate are suppressed in the setting of ETC dysfunction. This metabolic inflexibility forces a dependence on ETC-functional mitochondria and restoring acetyl-CoA production from pyruvate is sufficient to allow ETC-dysfunctional hepatocytes to proliferate. We propose that metabolic inflexibility within hepatocytes can be advantageous by limiting the expansion of ETC-dysfunctional cells.