Catálogo de publicaciones - revistas

<jats:title>Connecting caldera collapse</jats:title> <jats:p> The Kīlauea Volcano on the island of Hawai‘i erupted for 3 months in 2018. Neal <jats:italic>et al.</jats:italic> present a summary of the eruption sequence along with a variety of geophysical observations collected by the Hawaiian Volcano Observatory. The cyclic inflation, deflation, and eventual collapse of the summit was tied to lava eruption from lower East Rift Zone fissures. A total volume of 0.8 cubic kilometers of magma erupted, roughly the equivalent of 320,000 swimming pools, which matched the change in volume at the summit. </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="6425" page="367" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aav7046">367</jats:related-article> </jats:p>

<jats:title>Finding facts about fake news</jats:title> <jats:p> There was a proliferation of fake news during the 2016 election cycle. Grinberg <jats:italic>et al.</jats:italic> analyzed Twitter data by matching Twitter accounts to specific voters to determine who was exposed to fake news, who spread fake news, and how fake news interacted with factual news (see the Perspective by Ruths). Fake news accounted for nearly 6% of all news consumption, but it was heavily concentrated—only 1% of users were exposed to 80% of fake news, and 0.1% of users were responsible for sharing 80% of fake news. Interestingly, fake news was most concentrated among conservative voters. </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="6425" page="374" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aau2706">374</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6425" page="348" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aaw1315">348</jats:related-article> </jats:p>

<jats:title>Simulating transport with cold atoms</jats:title> <jats:p> Much can be learned about the nature of a solid from how charge and spin propagate through it. Transport experiments can also be performed in quantum simulators such as cold atom systems, in which individual atoms can be imaged using quantum microscopes. Now, two groups have investigated transport in the so-called Fermi-Hubbard model using a two-dimensional optical lattice filled with one fermionic atom per site (see the Perspective by Brantut). Moving away from half-filling to enable charge transport, Brown <jats:italic>et al.</jats:italic> found that the resistivity had a linear temperature dependence, not unlike that seen in the strange metal phase of cuprate superconductors. In a complementary study on spin transport, Nichols <jats:italic>et al.</jats:italic> observed spin diffusion driven by superexchange coupling. </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="6425" page="379" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aat4134">379</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6425" page="383" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aat4387">383</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6425" page="344" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aaw1326">344</jats:related-article> </jats:p>

<jats:title>Simulating transport with cold atoms</jats:title> <jats:p> Much can be learned about the nature of a solid from how charge and spin propagate through it. Transport experiments can also be performed in quantum simulators such as cold atom systems, in which individual atoms can be imaged using quantum microscopes. Now, two groups have investigated transport in the so-called Fermi-Hubbard model using a two-dimensional optical lattice filled with one fermionic atom per site (see the Perspective by Brantut). Moving away from half-filling to enable charge transport, Brown <jats:italic>et al.</jats:italic> found that the resistivity had a linear temperature dependence, not unlike that seen in the strange metal phase of cuprate superconductors. In a complementary study on spin transport, Nichols <jats:italic>et al.</jats:italic> observed spin diffusion driven by superexchange coupling. </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="6425" page="379" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aat4134">379</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6425" page="383" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aat4387">383</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6425" page="344" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aaw1326">344</jats:related-article> </jats:p>

<jats:title>Flexibility in gas absorption</jats:title> <jats:p> Soft materials such as porous coordination polymer (PCP) can exhibit temperature-dependent flexible motions of their internal pores that can assist in gas separation and storage. Gu <jats:italic>et al.</jats:italic> designed a copper-based PCP with a ligand that contains phenothiazine-5,5-dioxide. The entrances to the porous cages changed size with temperature, when these functional groups underwent flipping motions. The change in gate size could lead to high selectivity for gas absorption and enabled the separation of oxygen from argon and of ethylene from ethane as well as long-term gas storage under ambient conditions. </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="6425" page="387" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aar6833">387</jats:related-article> </jats:p>

<jats:title>Olefin shuffle for just a nickel</jats:title> <jats:p> Controlling the geometry of carbon-carbon double bonds is a central component of chemical manufacturing. One useful trick is to shift hydrogen atoms around to interconvert C=C isomers selectively. However, this approach typically requires precious metals. Kapat <jats:italic>et al.</jats:italic> now report that more-abundant nickel can catalyze rapid conversion of terminal olefins into internal olefins with high selectivity for trans geometry. The odd-electron nickel complex relies on a radical mechanism to shuttle hydrogen to the terminal carbon from the saturated carbon adjacent to the double bond. </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="6425" page="391" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aav1610">391</jats:related-article> </jats:p>

<jats:title> Hydrous CaCO <jats:sub>3</jats:sub> gets a new structure </jats:title> <jats:p> Calcium carbonate (CaCO <jats:sub>3</jats:sub> ) forms important minerals on Earth and is a model system for understanding crystal nucleation. Three different structures of CaCO <jats:sub>3</jats:sub> are known, along with two structures that are hydrated. Zou <jats:italic>et al.</jats:italic> found a third hydrated CaCO <jats:sub>3</jats:sub> structure formed from amorphous CaCO <jats:sub>3</jats:sub> in the presence of magnesium ions. The discovery illustrates the importance of amorphous precursors for producing new materials. </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="6425" page="396" related-article-type="in-this-issue" vol="363" xlink:href="10.1126/science.aav0210">396</jats:related-article> </jats:p>