作者:李言 来源:科学网微信公众号 发布时间:2023/11/12 20:29:11
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《科学》(20231110出版)一周论文导读

 

编译 | 李言

Science, 10 NOV 2023, Volume 382 Issue 6671

《科学》2023年11月10日,第382卷,6671期

 

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物理学Physics

Quantum control of trapped polyatomic molecules for eEDM searches

用于电子电偶极矩搜寻的捕获多原子分子的量子控制

▲ 作者:LOÏC ANDEREGG , NATHANIEL B. VILAS et al.

▲ 链接:https://www.science.org/doi/full/10.1126/science.adg8155

▲ 摘要:

在这项研究中,我们建立了氢氧化钙中单个量子态的相干控制,并展示了一种寻找电子电偶极矩(eEDM)的方法。在单量子态下制备了光学捕获的超冷氢氧化钙分子在电场中极化,并相干转移到eEDM敏感态,在此状态下进行了电子自旋进动测量。

为了延长相干时间,我们使用了具有可调谐的近零磁场灵敏度的eEDM敏感态。我们的研究结果为捕获多原子分子的eEDM搜寻开拓了一条路径。

▲ Abstract:

In this work, we established coherent control of individual quantum states in calcium monohydroxide (CaOH) and demonstrated a method for searching for the electron electric dipole moment (eEDM). Optically trapped, ultracold CaOH molecules were prepared in a single quantum state, polarized in an electric field, and coherently transferred into an eEDM-sensitive state where an electron spin precession measurement was performed. To extend the coherence time, we used eEDM-sensitive states with tunable, near-zero magnetic field sensitivity. Our results establish a path for eEDM searches with trapped polyatomic molecules.

机器学习Machine Learning

Prediction-powered inference

预测驱动推演

▲ 作者:ANASTASIOS N. ANGELOPOULOS, STEPHEN BATES et al.

▲ 链接:https://www.science.org/doi/full/10.1126/science.adi6000

▲ 摘要:

预测驱动推演是一种框架方法,当实验数据集补充了机器学习系统的预测时,它可以用于执行有效的统计推演。该框架使用简单算法,用于计算可证明有效的置信区间,如平均值、分位数、线性和逻辑回归系数,而无需对提供预测的机器学习算法进行任何假设。

此外,更准确的预测意味着更小的置信区间。预测驱动推演可以使研究人员利用机器学习得出有效的、更有效的数据效率结论。我们通过蛋白质组学、天文学、基因组学、遥感、人口普查分析和生态学的数据集已经证明了预测驱动推演的优势。

▲ Abstract:

Prediction-powered inference is a framework for performing valid statistical inference when an experimental dataset is supplemented with predictions from a machine-learning system. The framework yields simple algorithms for computing provably valid confidence intervals for quantities such as means, quantiles, and linear and logistic regression coefficients without making any assumptions about the machine-learning algorithm that supplies the predictions. Furthermore, more accurate predictions translate to smaller confidence intervals. Prediction-powered inference could enable researchers to draw valid and more data-efficient conclusions using machine learning. The benefits of prediction-powered inference were demonstrated with datasets from proteomics, astronomy, genomics, remote sensing, census analysis, and ecology.

材料科学Materials Science

Hierarchically structured passive radiative cooling ceramic with high solar reflectivity

具有高太阳反射率的分层结构被动辐射冷却陶瓷

▲ 作者:KAIXIN LIN, SIRU CHEN et al.

▲ 链接:https://www.science.org/doi/full/10.1126/science.adi4725

▲ 摘要:

我们开发了一种蜂窝陶瓷,可以实现高效的光散射和近乎完美的99.6%的太阳反射率。这些特性加上高热发射率,使陶瓷在室外环境中可以提供连续的亚环境制冷,中午的冷却功率大于每平方米130瓦,展示了全球范围的节能潜力。

陶瓷颜色、耐候性、机械坚固性和抑制莱顿弗罗斯特效应的能力等特点,确保其耐用性和通用性,从而促进其在各种应用中的商业化,尤其是建筑施工领域。

▲ Abstract:

We developed a cellular ceramic that can achieve highly efficient light scattering and a near-perfect solar reflectivity of 99.6%. These qualities, coupled with high thermal emissivity, allow the ceramic to provide continuous subambient cooling in an outdoor setting with a cooling power of >130 watts per square meter at noon, demonstrating energy-saving potential on a worldwide scale. The color, weather resistance, mechanical robustness, and ability to depress the Leidenfrost effect are key features ensuring the durable and versatile nature of the cooling ceramic, thereby facilitating its commercialization in various applications, particularly building construction.

生态学Ecolony

Plant size, latitude, and phylogeny explain within-population variability in herbivory

植物的大小、生长纬度和系统发育可以解释植食性种群内的变异

▲ 作者:THE HERBIVORY VARIABILITY NETWORK

▲ 链接:hhttps://www.science.org/doi/full/10.1126/science.adh8830

▲ 摘要:

植物和食草动物之间的相互作用是大多数生态系统的核心,但它们的力量是具有高度可变性的。一个系统内的可变性会影响植物—食草动物生物学的大多数方面,从生态稳定性到植物防御进化。然而,我们对影响变异的因素的理解受到数据缺乏的影响。

我们收集了横跨116°个纬度的790个站点、503种植物的食草性调查。通过这些数据,我们发现食草动物种群内的变异随纬度增加而增加,随植物大小而减少,并且具有系统发育结构。

因此,变异幅度的差异是植物—食草动物生物学如何在宏观尺度梯度上变化的核心。我们认为,增加对相互作用变异性的关注将促进对地球上生命模式的理解。

▲ Abstract:

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.

环境科学Environmental Science

Rising wildfire risk to houses in the United States, especially in grasslands and shrublands

美国房屋面临的野火风险不断上升,尤其在草地和灌木地地区

▲ 作者:OLKER C. RADELOFF, MIRANDA H. MOCKRIN et al.

▲ 链接:https://www.science.org/doi/full/10.1126/science.ade9223

▲ 摘要:

房屋面临的野火风险正在增加,特别是在荒地—城市地界(WUI),那里的荒地植被和房屋距离很近。值得注意的是,我们发现更多的美国房屋在草地和灌木丛火灾中被烧毁,而非森林火灾。

森林火灾更有可能造成破坏,但它们更少影响到荒地—城市地界。20世纪90年代以来,由于住房增长(造成额外的47%的房屋数量)和更多的烧毁地区(53%),受野火影响的房屋数量翻了一番。

大多数受影响的房屋都在荒地—城市地界,尽管没有以前那么快,但这些房屋在2010年代曾大幅增长。然而,任何荒地—城市地界的扩张都会增加房屋的野火风险,而更多的火灾会增加现有荒地—城市地界房屋的风险。

▲ Abstract:

Wildfire risks to homes are increasing, especially in the wildland-urban interface (WUI), where wildland vegetation and houses are in close proximity. Notably, we found that more houses are exposed to and destroyed by grassland and shrubland fires than by forest fires in the United States. Destruction was more likely in forest fires, but they burned less WUI. The number of houses within wildfire perimeters has doubled since the 1990s because of both housing growth (47% of additionally exposed houses) and more burned area (53%). Most exposed houses were in the WUI, which grew substantially during the 2010s (2.6 million new WUI houses), albeit not as rapidly as before. Any WUI growth increases wildfire risk to houses though, and more fires increase the risk to existing WUI houses.

人类学Anthropology

Early Homo erectus lived at high altitudes and produced both Oldowan and Acheulean tools

早期的直立人生活在高海拔地区,同时能生产奥杜威工具和阿舍利工具

▲ 作者:MARGHERITA MUSSI, MATTHEW M. SKINNER et al.

▲ 链接:https://www.science.org/doi/full/10.1126/science.add9115

▲ 摘要:

在非洲,与石器有直接联系的古人类遗骸很少,限制了将能人和直立人与特定的石器工业联系起来的研究发展。在埃塞俄比亚高地Garba IV (Melka Kunture) E层发现的婴儿下颌骨对这一问题至关重要,因为它与奥杜威石器产业直接相关。

在此,我们使用同步加速器成像检查了未萌出恒牙的内部形态,并确认其鉴定为直立人。

此外,我们使用修正的古地磁年龄来证明:(1)E层发现的下颌骨距今约200万年,是最早的直立人化石之一;(2)D层发现的下颌骨距今约195万年,其中保存有目前已知最早的阿舍利工具。

▲ Abstract:

In Africa, the scarcity of hominin remains found in direct association with stone tools has hindered attempts to link Homo habilis and Homo erectus with particular lithic industries. The infant mandible discovered in level E at Garba IV (Melka Kunture) on the highlands of Ethiopia is critical to this issue because of its direct association with an Oldowan lithic industry. Here, we used synchrotron imaging to examine the internal morphology of the unerupted permanent dentition and confirmed its identification as H. erectus. Additionally, we used revised paleomagnetic ages to show that (i) the mandible in level E is ~2 million years old and represents one of the earliest H. erectus fossils and that (ii) overlying level D, ~1.95 million years old, contains the earliest known Acheulean assemblage.

 
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