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<jats:title>Multifunction planar optics</jats:title> <jats:p> Specially designed two-dimensional (2D) arrays of nanometer-scale metallic antennas, or metasurfaces, may allow bulky optical components to be shrunk down to a planar device structure. Khorasaninejad <jats:italic>et al.</jats:italic> show that arrays of nanoscale fins of TiO can function as high-end optical lenses. At just a fraction of the size of optical objectives, such planar devices could turn your phone camera or your contact lens into a compound microscope. Maguid <jats:italic>et al.</jats:italic> interleaved sparse 2D arrays of metal antennas to get multifunctional behavior from the one planar device structure (see the Perspective by Litchinitser). The enhanced functionality of such designed metasurfaces could be used in sensing applications or to increase the communication capacity of nanophotonic networks. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue pp. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1190" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf6644">1190</jats:related-article> and <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1202" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf3417">1202</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1177" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf8391">1177</jats:related-article> </jats:p>

<jats:title>A close-up look at eight water molecules</jats:title> <jats:p> A raindrop may look small, but it contains far too much water to model with the highest chemical precision. Theorists rely on studies of clusters with just a few molecules to enhance their understanding of the quantum-mechanical forces at play in the liquid. Cole <jats:italic>et al.</jats:italic> now report a high-resolution spectrum in the terahertz regime of the eight-membered cluster. By resolving 99 absorption lines associated with a collective torsional mode, the authors distinguish prolate and oblate isomers that are very similar in energy. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1194" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aad8625">1194</jats:related-article> </jats:p>

<jats:title>A radio view into Jupiter's atmosphere</jats:title> <jats:p> Jupiter's atmosphere is a complex system of belts, layers, storms, and cloud systems. de Pater <jats:italic>et al.</jats:italic> used Earth-bound radio observations to peer beneath its surface. Previous radio studies have been limited to average properties at each latitude, but the new observations allow a full two-dimensional view. This can be related to features (such as storms) seen in visible or infrared images. The results aid our understanding of gas giant atmospheres and will provide important context for the Juno spacecraft that arrives at Jupiter in July 2016. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1198" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf2210">1198</jats:related-article> </jats:p>

<jats:title>Multifunction planar optics</jats:title> <jats:p> Specially designed two-dimensional (2D) arrays of nanometer-scale metallic antennas, or metasurfaces, may allow bulky optical components to be shrunk down to a planar device structure. Khorasaninejad <jats:italic>et al.</jats:italic> show that arrays of nanoscale fins of TiO can function as high-end optical lenses. At just a fraction of the size of optical objectives, such planar devices could turn your phone camera or your contact lens into a compound microscope. Maguid <jats:italic>et al.</jats:italic> interleaved sparse 2D arrays of metal antennas to get multifunctional behavior from the one planar device structure (see the Perspective by Litchinitser). The enhanced functionality of such designed metasurfaces could be used in sensing applications or to increase the communication capacity of nanophotonic networks. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue pp. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1190" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf6644">1190</jats:related-article> and <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1202" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf3417">1202</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1177" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf8391">1177</jats:related-article> </jats:p>

<jats:title>Orbitals and charge go their separate ways</jats:title><jats:p>In certain materials at very low temperatures, an electron's spin can separate from its charge, zooming through the crystal in the form of a “spinon.” Such materials are usually one-dimensional, and their atoms have spins of 1/2. Wu<jats:italic>et al.</jats:italic>observed related behavior in a three-dimensional metal, Yb<jats:sub>2</jats:sub>Pt<jats:sub>2</jats:sub>Pb, where the Yb ions have a large magnetic moment that has its origin in the electrons' orbital motion rather than their spin. Neutron-scattering measurements indicated that these large magnetic moments can flip their direction through an exchange process similar to the one that occurs in spin 1/2 systems. This process results in effective charge-orbital separation.</jats:p><jats:p><jats:italic>Science</jats:italic>, this issue p.<jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1206" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf0981">1206</jats:related-article></jats:p>

<jats:title>Artificial photosynthesis steps up</jats:title> <jats:p> Photosynthesis fixes CO <jats:sub>2</jats:sub> from the air by using sunlight. Industrial mimics of photosynthesis seek to convert CO <jats:sub>2</jats:sub> directly into biomass, fuels, or other useful products. Improving on a previous artificial photosynthesis design, Liu <jats:italic>et al.</jats:italic> combined the hydrogen-oxidizing bacterium <jats:italic>Raistonia eutropha</jats:italic> with a cobalt-phosphorus water-splitting catalyst. This biocompatible self-healing electrode circumvented the toxicity challenges of previous designs and allowed it to operate aerobically. When combined with solar photovoltaic cells, solar-to-chemical conversion rates should become nearly an order of magnitude more efficient than natural photosynthesis. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1210" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf5039">1210</jats:related-article> </jats:p>

<jats:title>Microplastic's triple threat</jats:title> <jats:p> The billions of tons of plastics that we release into the environment for the most part do not biodegrade. But they do degrade, breaking into ever smaller particles that end up in the oceans. Lönnstedt <jats:italic>et al.</jats:italic> show that the impacts of these microplastics are multifold (see the Perspective by Rochman). Eurasian perch larvae exposed to microplastics were less active, less responsive to predator cues, more likely to be eaten, and less likely to thrive—preferring to eat plastic rather than their natural prey. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1213" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aad8828">1213</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1172" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf8697">1172</jats:related-article> </jats:p>

<jats:title>Making cardiac cells from fibroblasts</jats:title> <jats:p> Reprogramming noncardiac cells into functional cardiomyocytes without any genetic manipulation could open up new avenues for cardiac regenerative therapies. Cao <jats:italic>et al.</jats:italic> identified a combination of nine small molecules that could epigenetically activate human fibroblasts, efficiently reprogramming them into chemically induced cardiomyocytes (ciCMs). The ciCMs contracted uniformly and resembled human cardiomyocytes. This method may be adapted for reprogramming multiple cell types and have important implications in regenerative medicine. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1216" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aaf1502">1216</jats:related-article> </jats:p>

<jats:title>A nuclear power source in the cell</jats:title> <jats:p> DNA is packaged onto nucleosomes, the principal component of chromatin. This chromatin must be remodeled to allow gene transcription, DNA replication, and DNA repair machineries access to the enclosed DNA. Chromatin-remodeling complexes require high levels of cellular energy to do their job. Wright <jats:italic>et al.</jats:italic> show that the energy needed to remodel chromatin can be derived from a source, poly-ADP-ribose, in the cell nucleus, rather than by diffusion of ATP from mitochondria in the cytoplasm, the usual powerhouse of the cell. Poly-ADP-ribose is converted to ADP-ribose and then to ATP, which can be used to fuel chromatin remodeling within the nucleus. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1221" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aad9335">1221</jats:related-article> </jats:p>

<jats:title>TT-Seq maps a transient transcriptome</jats:title> <jats:p> RNA expression is related to protein abundance and cellular function. However, the amounts of RNA generated at any one time-point have been difficult to determine. Schwalb <jats:italic>et al.</jats:italic> developed a method, transient transcriptome sequencing (TT-Seq), to collect and sequence all RNA segments synthesized over 5 minutes. Because 5 minutes is not long enough to fully degrade even the most transient RNA, this method can detect the synthesis of most RNA without bias. Applying this method to human K562 cells, TT-Seq detected thousands of noncoding transcripts, providing a snapshot of RNA synthesis rates and RNA half-lives, and full-length maps of short-lived RNAs such as enhancers and short intergenic noncoding RNAs. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6290" page="1225" related-article-type="in-this-issue" vol="352" xlink:href="10.1126/science.aad9841">1225</jats:related-article> </jats:p>