Catálogo de publicaciones - revistas

<jats:title>Genetic variants provide a nurturing environment</jats:title> <jats:p> Genetic variants in parents may affect the fitness of their offspring, even if the child does not carry the allele. This indirect effect is referred to as “genetic nurture.” Kong <jats:italic>et al.</jats:italic> used data from genome-wide association studies of educational attainment to construct polygenic scores for parents that only considered the nontransmitted alleles (see the Perspective by Koellinger and Harden). The findings suggest that genetic nurture is ultimately due to genetic variation in the population and is mediated by the environment that parents create for their children. </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="6374" page="424" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aan6877">424</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6374" page="386" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aar6429">386</jats:related-article> </jats:p>

<jats:title>A reaction screen in flowing solvent</jats:title> <jats:p> Chemists charged with manufacturing pharmaceuticals have recently been exploring the efficiency advantages of continuous flow techniques. Perera <jats:italic>et al.</jats:italic> now show that a flow apparatus can also accelerate reaction optimization earlier in the drug discovery process. They modified a high-performance liquid chromatography system to screen a wide variety of solvent, ligand, and base combinations to optimize carbon-carbon bond formation. Injecting stock solution aliquots of the catalyst and reactants into a carrier solvent stream let the authors vary the main solvent efficiently and scale up the optimal conditions for product isolation. </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="6374" page="429" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aap9112">429</jats:related-article> </jats:p>

<jats:title>How to get two bonds for the price of one</jats:title> <jats:p> For more than a century, we have known how to couple aryl chlorides at the sites of their C-Cl bonds to form a single C-C bond. Koga <jats:italic>et al.</jats:italic> found that palladium catalysis can instead activate these C-Cl bonds to attack nearby aromatic C-H bonds in a terphenyl molecular framework. The reaction thereby produces a new ring, fused to the original rings on either side. Polycyclic compounds of this sort are of particular interest in optoelectronics research because of their expansive electron delocalization. </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="6374" page="435" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aap9801">435</jats:related-article> </jats:p>

<jats:title>Building an essential quantum component</jats:title> <jats:p> To build a universal quantum computer—the kind that can handle any computational task you throw at it—an essential early step is to demonstrate the so-called CNOT gate, which acts on two qubits. Zajac <jats:italic>et al.</jats:italic> built an efficient CNOT gate by using electron spin qubits in silicon quantum dots, an implementation that is especially appealing because of its compatibility with existing semiconductor-based electronics (see the Perspective by Schreiber and Bluhm). To showcase the potential, the authors used the gate to create an entangled quantum state called the Bell state. </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="6374" page="439" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aao5965">439</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6374" page="393" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aar6209">393</jats:related-article> </jats:p>

<jats:title>Nanoscale chiral valley-photon interface</jats:title> <jats:p> Occupation of different valleys within the band structure of some materials can be used to encode information. That information is typically encoded in terms of the chirality or polarization of emitted photons. Gong <jats:italic>et al.</jats:italic> combined a plasmonic silver nanowire with a flake of the transition metal dichalcogenide WS <jats:sub>2</jats:sub> to form a nanophotonic platform for the transfer of solid-state spin into optical information over mesoscopic distances. The direction of light emission from the nanowire was strongly dependent on the spin-orbit coupling of light and the WS2 layer. Such a highly efficient interface should prove useful for developing valleytronics into a practical on-chip technology. </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="6374" page="443" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aan8010">443</jats:related-article> </jats:p>

<jats:title>A framework for more ductile magnesium</jats:title> <jats:p> Development of ductile magnesium alloys is key to their use in reducing the weight of vehicles and other applications. Wu <jats:italic>et al.</jats:italic> tackle this issue by determining the underlying mechanisms in unprocessed magnesium alloys. Dilute amounts of solutes enhanced certain ductility-improving mechanisms over ones that cause brittle fracture. From this, the authors developed a theory that may be helpful for screening the large number of potential magnesium alloy compositions. </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="6374" page="447" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aap8716">447</jats:related-article> </jats:p>

<jats:title>Tuning the atomic pairing</jats:title> <jats:p> Cold atomic gases are extremely flexible systems; the ability to tune interactions between fermionic atoms can, for example, cause the gas to undergo a crossover from weakly interacting fermions to weakly interacting bosons via a strongly interacting unitary regime. Murthy <jats:italic>et al.</jats:italic> studied this crossover in a gas of fermions confined to two dimensions. The formation of atomic pairs occurred at much higher temperatures in the unitary regime than previously thought. </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="6374" page="452" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aan5950">452</jats:related-article> </jats:p>

<jats:title>Earliest modern humans out of Africa</jats:title><jats:p>Recent paleoanthropological studies have suggested that modern humans migrated from Africa as early as the beginning of the Late Pleistocene, 120,000 years ago. Hershkovitz<jats:italic>et al.</jats:italic>now suggest that early modern humans were already present outside of Africa more than 55,000 years earlier (see the Perspective by Stringer and Galway-Witham). During excavations of sediments at Mount Carmel, Israel, they found a fossil of a mouth part, a left hemimaxilla, with almost complete dentition.</jats:p><jats:p>The sediments contain a series of well-defined hearths and a rich stone-based industry, as well as abundant animal remains. Analysis of the human remains, and dating of the site and the fossil itself, indicate a likely age of at least 177,000 years for the fossil—making it the oldest member of the<jats:italic>Homo sapiens</jats:italic>clade found outside Africa.</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="6374" page="456" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aap8369">456</jats:related-article>; see also p.<jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6374" page="389" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aas8954">389</jats:related-article></jats:p>

<jats:title>Corals wrapped in plastic</jats:title> <jats:p> Coral reefs provide vital fisheries and coastal defense, and they urgently need protection from the damaging effects of plastic waste. Lamb <jats:italic>et al.</jats:italic> surveyed 159 coral reefs in the Asia-Pacific region. Billions of plastic items were entangled in the reefs. The more spikey the coral species, the more likely they were to snag plastic. Disease likelihood increased 20-fold once a coral was draped in plastic. Plastic debris stresses coral through light deprivation, toxin release, and anoxia, giving pathogens a foothold for invasion. </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="6374" page="460" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aar3320">460</jats:related-article> </jats:p>

<jats:title>The neuronal population is the key unit</jats:title> <jats:p> The responses of pairs of neurons to repeated presentations of the same stimulus are typically correlated, and an identical neuronal population can perform many functions. This suggests that the relevant units of computation are not single neurons but subspaces of the complete population activity. To test this idea, Ni <jats:italic>et al.</jats:italic> measured the relationship between neuronal population activity and performance in monkeys. They investigated attention, which improves perception of attended stimuli, and perceptual learning, which improves perception of well-practiced stimuli. These two processes operate on different time scales and are usually studied using different perceptual tasks. Manipulation of attention and learning in the same behavioral trials and the same neuronal populations revealed the dimensions of population activity that matter most for behavior. </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="6374" page="463" related-article-type="in-this-issue" vol="359" xlink:href="10.1126/science.aao0284">463</jats:related-article> </jats:p>