Catálogo de publicaciones - revistas

<jats:title>Flying fast and free</jats:title> <jats:p> Insect flight can be fast and agile, making it hard to study its detailed aerodynamics. Karásek <jats:italic>et al.</jats:italic> designed an untethered, flapping-wing robot with impressive agility that can mimic fruitfly maneuvers (see the Perspective by Ruffier). They studied the robot's motion during rapid banked turns, which revealed that passive motion through the turn generated yaw torque coupling. This correcting yaw rotation propelled the robot toward the escape heading needed for effective turning. </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="6407" page="1089" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat0350">1089</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6407" page="1073" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aau7350">1073</jats:related-article> </jats:p>

<jats:title>Tailoring tandem organics</jats:title> <jats:p> Tandem solar cells can boost efficiency by using a wider range of the solar spectrum. The bandgap of organic semiconductors can be tuned over a wide range, but, for a two-terminal device that directly connects the cells, the currents produced must be nearly equal. Meng <jats:italic>et al.</jats:italic> used a semiempirical analysis to choose well-matched top- and bottom-cell active layers. They used solution processing to fabricate an inverted tandem device that has a power conversion efficiency as high as 17.4%. </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="6407" page="1094" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat2612">1094</jats:related-article> </jats:p>

<jats:title>Metals brought together do more</jats:title> <jats:p> Enzymatic reduction of oxyanions such as sulfite (SO <jats:sub>3</jats:sub> <jats:sup>2−</jats:sup> ) requires the delivery of multiple electrons and protons, a feat accomplished by cofactors tailored for catalysis and electron transport. Replicating this strategy in protein scaffolds may expand the range of enzymes that can be designed de novo. Mirts <jats:italic>et al.</jats:italic> selected a scaffold protein containing a natural heme cofactor and then engineered a cavity suitable for binding a second cofactor—an iron-sulfur cluster (see the Perspective by Lancaster). The resulting designed enzyme was optimized through rational mutation into a catalyst with spectral characteristics and activity similar to that of natural sulfite reductases. </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="6407" page="1098" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat8474">1098</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6407" page="1071" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aau7754">1071</jats:related-article> </jats:p>

<jats:title>Going quantum with metamaterials</jats:title> <jats:p> Metasurfaces should allow wafer-thin surfaces to replace bulk optical components. Two reports now demonstrate that metasurfaces can be extended into the quantum optical regime. Wang <jats:italic>et al.</jats:italic> determined the quantum state of multiple photons by simply passing them through a dielectric metasurface, scattering them into single-photon detectors. Stav <jats:italic>et al.</jats:italic> used a dielectric metasurface to generate entanglement between spin and orbital angular momentum of single photons. The results should aid the development of integrated quantum optic circuits operating on a nanophotonic platform. </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="6407" page="1104" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat8196">1104</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6407" page="1101" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat9042">1101</jats:related-article> </jats:p>

<jats:title>Going quantum with metamaterials</jats:title> <jats:p> Metasurfaces should allow wafer-thin surfaces to replace bulk optical components. Two reports now demonstrate that metasurfaces can be extended into the quantum optical regime. Wang <jats:italic>et al.</jats:italic> determined the quantum state of multiple photons by simply passing them through a dielectric metasurface, scattering them into single-photon detectors. Stav <jats:italic>et al.</jats:italic> used a dielectric metasurface to generate entanglement between spin and orbital angular momentum of single photons. The results should aid the development of integrated quantum optic circuits operating on a nanophotonic platform. </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="6407" page="1104" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat8196">1104</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6407" page="1101" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat9042">1101</jats:related-article> </jats:p>

<jats:title>Mapping global deforestation patterns</jats:title> <jats:p> Forest loss is being driven by various factors, including commodity production, forestry, agriculture, wildfire, and urbanization. Curtis <jats:italic>et al.</jats:italic> used high-resolution Google Earth imagery to map and classify global forest loss since 2001. Just over a quarter of global forest loss is due to deforestation through permanent land use change for the production of commodities, including beef, soy, palm oil, and wood fiber. Despite regional differences and efforts by governments, conservationists, and corporations to stem the losses, the overall rate of commodity-driven deforestation has not declined since 2001. </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="6407" page="1108" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aau3445">1108</jats:related-article> </jats:p>

<jats:title>Rapid, long-distance signaling in plants</jats:title> <jats:p> A plant injured on one leaf by a nibbling insect can alert its other leaves to begin anticipatory defense responses. Working in the model plant <jats:italic>Arabidopsis</jats:italic> , Toyota <jats:italic>et al.</jats:italic> show that this systemic signal begins with the release of glutamate, which is perceived by glutamate receptor–like ion channels (see the Perspective by Muday and Brown-Harding). The ion channels then set off a cascade of changes in calcium ion concentration that propagate through the phloem vasculature and through intercellular channels called plasmodesmata. This glutamate-based long-distance signaling is rapid: Within minutes, an undamaged leaf can respond to the fate of a distant leaf. </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="6407" page="1112" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat7744">1112</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6407" page="1068" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aau9813">1068</jats:related-article> </jats:p>

<jats:title>Bird forecast</jats:title> <jats:p>Billions of birds migrate across the globe each year, and, in our modern environment, many collide with human-made structures and vehicles. The ability to predict peak timing and locations of migratory events could greatly improve our ability to reduce such collisions. Van Doren and Horton used radar and atmospheric-condition data to predict the peaks and flows of migrating birds across North America. Their models predicted, with high accuracy, patterns of bird migration at altitudes between 0 and 3000 meters and as far as 7 days in advance, a time span that will allow for planning and preparation around these important events.</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="6407" page="1115" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aat7526">1115</jats:related-article> </jats:p>

<jats:title>ER-SURF protein import into mitochondria</jats:title> <jats:p> Eukaryotic cells contain membrane-bound organelles, defined by distinct protein compositions. Almost all cellular proteins are synthesized in the cytosol, and thus, organelle-resident proteins must be directed to their appropriate location after synthesis. Working in yeast, Hansen <jats:italic>et al.</jats:italic> identified a protein-targeting paradigm termed ER-SURF, in which the membrane expanse of the endoplasmic reticulum (ER) serves as a “capture net” for mitochondrial proteins. This process productively redirected mitochondrial precursor proteins for efficient mitochondrial import. Thus, two distinct organelles, once thought to be mutually exclusive protein destinations, can cooperate during protein targeting. </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="6407" page="1118" related-article-type="in-this-issue" vol="361" xlink:href="10.1126/science.aar8174">1118</jats:related-article> </jats:p>