Catálogo de publicaciones - revistas

<jats:title>Protecting entangled pairs</jats:title> <jats:p> Photons are readily generated, are fast and can travel vast distances, and are ideal carriers of quantum information. Practical applications, such as quantum computing, will likely be based on an optical-chip platform and require the manipulation of multiphoton states. The inevitable scattering and loss of photons in such a platform would be detrimental for application. Blanco-Redondo <jats:italic>et al.</jats:italic> show how a specially designed optical circuit based on topology can offer protection for propagating biphoton states. The results show that topological design consideration could provide the desired robustness required for quantum optical circuitry. </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="6414" page="568" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau4296">568</jats:related-article> </jats:p>

<jats:title>Snapshots of a phase transition</jats:title> <jats:p> Time-resolved x-ray scattering can be used to investigate the dynamics of materials during the switch from one structural phase to another. So far, methods provide an ensemble average and may miss crucial aspects of the detailed mechanisms at play. Wall <jats:italic>et al.</jats:italic> used a total-scattering technique to probe the dynamics of the ultrafast insulator-to-metal transition of vanadium dioxide (VO <jats:sub>2</jats:sub> ) (see the Perspective by Cavalleri). Femtosecond x-ray pulses provide access to the time- and momentum-resolved dynamics of the structural transition. Their results show that the photoinduced transition is of the order-disorder type, driven by an ultrafast change in the lattice potential that suddenly unlocks the vanadium atoms and yields large-amplitude uncorrelated motions, rather than occurring through a coherent displacive mechanism. </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="6414" page="572" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau3873">572</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6414" page="525" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav2019">525</jats:related-article> </jats:p>

<jats:title>Predicting hosts and vectors</jats:title> <jats:p> During outbreaks of mysterious infections, events can rapidly become dangerous and confusing. A combination of increasing experience with outbreaks and genome-sequencing technology now means the pathogen can often be identified within days. But for some of the most frightening viral pathogens, the originating hosts and possible vectors often remain obscure. Babayan <jats:italic>et al.</jats:italic> took sequence data from more than 500 single-stranded RNA viruses (see the Perspective by Woolhouse) and used machine-learning algorithms to extract evolutionary signals imprinted in the virus sequence that offer information about its original hosts and if an arthropod vector, and what type, plays a part in the virus's natural ecology. </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="6414" page="577" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aap9072">577</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6414" page="524" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav4265">524</jats:related-article> </jats:p>

<jats:title>East Asian monsoon mysteries</jats:title> <jats:p> What exactly does the oxygen isotopic composition of speleothems tell us about the East Asian monsoon? They provide magnificent, detailed records of hydroclimate, but precisely what aspects of hydroclimate they record is unclear. Zhang <jats:italic>et al.</jats:italic> present data from two speleothems from central eastern China for the period from 21,000 to 10,000 years ago and suggest that the cause of the oxygen isotopic variability that they observe is more complex than simple changes in monsoon strength or intensity (see the Perspective by McGee). Alternatively, this variation may reflect the lengths of various phases of the monsoon and the regional heterogeneity of the East Asian hydroclimate. </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="6414" page="580" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aat9393">580</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6414" page="518" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav5280">518</jats:related-article> </jats:p>

<jats:title>Posture in the brain</jats:title> <jats:p> Our understanding of the neural basis of motor control originates in studies of eye, hand, and arm movements in primates. Mimica <jats:italic>et al.</jats:italic> investigated neuronal representations of body postures in the posterior parietal and frontal motor cortices with three-dimensional tracking of freely moving rodents (see the Perspective by Chen). Both brain regions represented posture rather than movements and self-motion. Decoding the activity of neurons in the two regions accurately predicted an animal's posture. </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="6414" page="584" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau2013">584</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6414" page="520" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav3819">520</jats:related-article> </jats:p>

<jats:title>Gut microbiota selects fungi</jats:title> <jats:p> Fungi, such as <jats:italic>Candida albicans</jats:italic> , are found in the mammalian gut, but we know little about what they are doing there. Tso <jats:italic>et al.</jats:italic> put <jats:italic>C. albicans</jats:italic> under evolutionary pressure by serial passage in mice that were treated with antibiotics and were thus lacking gut bacteria (see the Perspective by d'Enfert). Passage accelerated fungal mutation, especially around the <jats:italic>FLO8</jats:italic> gene, resulting in low-virulence phenotypes unable to form hyphae. Nevertheless, these phenotypes stimulated proinflammatory cytokines and conferred transient cross-protection against several other gut inhabitants. However, if an intact microbiota was present, only the virulent hyphal forms persisted. </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="6414" page="589" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aat0537">589</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6414" page="523" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav3374">523</jats:related-article> </jats:p>

<jats:title>Nucleosomal DNA transcription</jats:title> <jats:p> In eukaryotes, the basic chromatin unit nucleosome stalls RNA polymerase II (RNAPII) when it transcribes genetic information on DNA. Using cryo–electron microscopy, Kujirai <jats:italic>et al.</jats:italic> explored seven structures of the RNAPII-nucleosome complex, in which RNAPII pauses at four locations on the nucleosome. These serial snapshots of the RNAPII progression reveal the molecular mechanism of how RNAPII peels the nucleosomal DNA off the histone stepwise. </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="6414" page="595" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau9904">595</jats:related-article> </jats:p>

<jats:title>Durable influenza protection</jats:title> <jats:p> Vaccines are indispensable for the control and prevention of influenza, but there are several challenges to efficacy. Some individuals respond poorly to vaccination, and virus variation makes targeting optimal antigens difficult. Broadly neutralizing antibodies are one solution, but they have their own pitfalls, including limited cross-reactivity to both influenza A and B strains and the need for repeated injections. Now, Laursen <jats:italic>et al.</jats:italic> have developed multidomain antibodies with breadth and potency. Administered intranasally to mice with an adeno-associated virus vector, the antibodies provided durable and continuous protection from a panoply of influenza strains. </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="6414" page="598" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aaq0620">598</jats:related-article> </jats:p>

<jats:p>A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.</jats:p>