Catálogo de publicaciones - revistas

<jats:title>Water's surface dielectric</jats:title> <jats:p> Theoretical studies predict that the inhibition of rotational motion of water near a solid surface will decrease its local dielectric constant. Fumagalli <jats:italic>et al.</jats:italic> fabricated thin channels in insulating hexagonal boron nitride on top of conducting graphene layers (see the Perspective by Kalinin). The channels, which varied in height from 1 to 300 nanometers, were filled with water and capped with a boron nitride layer. Modeling of the capacitance measurements made with an atomic force microscope tip revealed a surface-layer dielectric constant of 2, compared with the bulk value of 80 for water. </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="6395" page="1339" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aat4191">1339</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6395" page="1302" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aat9875">1302</jats:related-article> </jats:p>

<jats:title>Testing General Relativity on galaxy scales</jats:title> <jats:p> Einstein's theory of gravity, General Relativity (GR), has been tested precisely within the Solar System. However, it has been difficult to test GR on the scale of an individual galaxy. Collett <jats:italic>et al.</jats:italic> exploited a nearby gravitational lens system, in which light from a distant galaxy (the source) is bent by a foreground galaxy (the lens). Mass distribution in the lens was compared with the curvature of space-time around the lens, independently determined from the distorted image of the source. The result supports GR and eliminates some alternative theories of gravity. </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="6395" page="1342" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aao2469">1342</jats:related-article> </jats:p>

<jats:title>The noblewoman's ape</jats:title> <jats:p> Human activities are causing extinctions across a wide array of taxa. Yet there has been no evidence of humans directly causing extinction among our relatives, the apes. Turvey <jats:italic>et al.</jats:italic> describe a species of gibbon found in a 2200- to 2300-year-old tomb ascribed to a Chinese noblewoman. This previously unknown species was likely widespread, may have persisted until the 18th century, and may be the first ape species to have perished as a direct result of human activities. This discovery may also indicate the existence of unrecognized primate diversity across Asia. </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="6395" page="1346" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aao4903">1346</jats:related-article> </jats:p>

<jats:title>Rebalancing strength between synapses</jats:title> <jats:p> Activation of a neuronal pathway is often associated with inhibition of surrounding pathways. How locally coordinated synaptic plasticity occurs in vivo is not known, nor is its role in shaping neuronal responses. El-Boustani <jats:italic>et al.</jats:italic> paired optogenetic stimulation of single neurons with a visual input and were able to shift the neuron's receptive field toward the target location. Spines that expressed structural long-term potentiation had receptive fields overlapping the target stimulus but were surrounded by spines that expressed receptive fields away from the target. </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="6395" page="1349" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aao0862">1349</jats:related-article> </jats:p>

<jats:title>Hybrid camouflage variation</jats:title> <jats:p> Snowshoe hares molt from a brown coat to a white coat in winter. In some populations, however, where winter snow is less extensive, hares molt from a brown coat to a brown coat. Jones <jats:italic>et al.</jats:italic> show that regulation of the pigmentation gene <jats:italic>Agouti</jats:italic> is responsible for the winter coat color change. Hybridization with jackrabbits has led to introgression around this gene that facilitates the brown winter morph. Hybridization appears to have provided important adaptive variation to the snowshoe hare. </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="6395" page="1355" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aar5273">1355</jats:related-article> </jats:p>

<jats:title>Surface antibody maturation</jats:title> <jats:p> Affinity maturation in B cells generates antibodies with increasingly enhanced antigen-binding properties. Imkeller <jats:italic>et al.</jats:italic> investigated the maturation of human B cells that express protective antibodies against the circumsporozoite protein of the malaria-causing parasite <jats:italic>Plasmodium falciparum</jats:italic> (PfCSP). The repetitive structure of PfCSP induces mutations in B cells, facilitating direct interactions between two repeat-bound antibodies against PfCSP, which enhance antigen affinity and B cell activation. Such interactions may optimize binding and promote clustering of surface antibodies in general. </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="6395" page="1358" related-article-type="in-this-issue" vol="360" xlink:href="10.1126/science.aar5304">1358</jats:related-article> </jats:p>

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