Microscopic robots with features comparable with the wavelength of light offer new ways of probing the microscopic world and controlling light at the microscale. We introduce a new class of magnetically controlled microscopic robots (microbots) that operate at the visible-light diffraction limit, which we term diffractive robots. We combined nanometer-thick mechanical membranes, programmable nanomagnets, and diffractive optical elements to create untethered microbots small enough to diffract visible light and flexible enough to undergo complex reconfigurations in millitesla-scale magnetic fields. We demonstrated their applications, including subdiffractive imaging by using a variant of structured illumination microscopy, tunable diffractive optical elements for beam steering and focusing, and force sensing with piconewton sensitivity.
化学和物理学Chemistry & Physics
Aromatic-aliphatic hydrocarbon separation with oriented monolayer polyhedral membrane
定向单层多面体膜分离芳烃—脂肪族烃
▲ 作者：HAO SUN, NAIXIN WANG, YINGHUI XU, FENGKAI WANG, JUN LU, HUANTING WANG, AND QUAN-FU AN
We examined the impact of exposure to sugar restrictions within 1000 days after conception on type 2 diabetes and hypertension, leveraging quasi-experimental variation from the end of the United Kingdom’s sugar rationing in September 1953. Rationing restricted sugar intake to levels within current dietary guidelines, and consumption nearly doubled immediately after rationing ended. Using an event study design with UK Biobank data comparing adults conceived just before or after rationing ended, we found that early-life rationing reduced type 2 diabetes and hypertension risk by about 35 and 20% and delayed disease onset by 4 and 2 years, respectively. Protection was evident with in utero exposure and increased with postnatal sugar restriction, especially after 6 months, when eating of solid foods likely began. In utero sugar rationing alone accounted for about one-third of the risk reduction.
信息学和机器人Informatics & Robotics
Misinformation exploits outrage to spread online
虚假信息利用愤怒在网上传播
▲ 作者：KILLIAN L. MCLOUGHLIN, WILLIAM J. BRADY, ADEN GOOLSBEE, BEN KAISER, KATE KLONICK, AND M. J. CROCKETT
Low-dimensional quantum systems can host anyons, particles with exchange statistics that are neither bosonic nor fermionic. However, the physics of anyons in one dimension remains largely unexplored. In this work, we realize Abelian anyons in one dimension with arbitrary exchange statistics using ultracold atoms in an optical lattice, where we engineer the statistical phase through a density-dependent Peierls phase. We explore the dynamical behavior of two anyons undergoing quantum walks and observe the anyonic Hanbury Brown–Twiss effect as well as the formation of bound states without on-site interactions. Once interactions are introduced, we observe spatially asymmetric transport in contrast to the symmetric dynamics of bosons and fermions. Our work forms the foundation for exploring the many-body behavior of one-dimensional anyons.
Misinformation remains a major threat to US democratic integrity,national security, and public health. However, social media platforms struggle to curtail the spread of the harmful but engaging content. Across platforms, McLoughlin et al. examined the role of emotions, specifically moral outrage (a mixture of disgust and anger), in the diffusion of misinformation. Compared with trustworthy news sources, posts from misinformation sources evoked more angry reactions and outrage than happy or sad sentiments. Users were motivated to reshare content that evoked outrage and shared it without reading it first to discern accuracy. Interventions that solely emphasize sharing accurately may fail to curb misinformation because users may share outrageous, inaccurate content to signal their moral positions or loyalty to political groups.
Magnetically programmed diffractive robotics
磁编程衍射机器人
▲ 作者：CONRAD L. SMART, TANNER G. PEARSON, ZEXI LIANG, MELODY X. LIM, MOHAMED I. ABDELRAHMAN, FRANCESCO MONTICONE, ITAI COHEN, AND PAUL L. MCEUEN
Aromatic-aliphatic hydrocarbon separation is a challenging but important industrial process. Pervaporation membrane technology has the potential for separating these mixtures. We developed an oriented monolayer polyhedral (OMP) membrane that consists of a monolayer of ordered polyhedral particles and is anchored by hyperbranched polymers. It contains a high density of straight, selective nanochannels, enabling the preferential transport of aromatic molecules. Compared with traditional mixed-matrix membranes with random orientations, the OMP membrane improves the pervaporation separation index for aromatic-aliphatic hydrocarbon mixtures with C6 and C7 compounds, surpassing the performance of existing membranes by 3 to 10 times. This high performance demonstrates the potential of OMP membranes for hydrocarbon molecular separation and their application in the value-added separation of naphtha feedstocks.
Realization of one-dimensional anyons with arbitrary statistical phase
具有任意统计相位的一维任意子的实现
▲ 作者：JOYCE KWAN, PERRIN SEGURA, YANFEI LI, SOOSHIN KIM, ALEXEY V. GORSHKOV, ANDRé ECKARDT, BRICE BAKKALI-HASSANI, AND MARKUS GREINER
Anyone who exercises regularly knows what it is like to feel intensely thirsty. This powerful drive for water is common within mammals and ensures that our physiological need for water is met. In animals that hibernate, however, drinking and thirst are suppressed for months. Junkins et al. looked at this phenomenon in the thirteen-lined ground squirrel, a well-studied hibernating rodent, and found that their months-long suppression of thirst comes even in the face of physiological indicators of fluid deficit. This suppression is mediated by reduced activity of neurons in the circumventricular organs, which experience reduced function in winter.
Exposure to sugar rationing in the first 1000 days of life protected against chronic disease
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