Catálogo de publicaciones - revistas

<jats:title>Transporter layers improve stability</jats:title> <jats:p> Although perovskite solar cells can have power conversion efficiencies exceeding 20%, they can have limited thermal and ultraviolet irradiation stability. This is in part because of the materials used to extract the charge carriers (electrons and holes) from the active layer. Arora <jats:italic>et al.</jats:italic> replaced organic hole transporter layers with CuCSN to improve thermal stability. Device lifetime was enhanced when a conducting reduced graphene oxide spacer was added between the CuSCN layer and the gold electrode. </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="6364" page="768" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aam5655">768</jats:related-article> </jats:p>

<jats:title>Topological or trivial?</jats:title> <jats:p> Evidence for Majorana bound states (MBS), which are expected to provide a platform for topological quantum computing, has been found in several material systems. Typically, the experimental signature is a peak in the spectrum at zero energy, but mechanisms other than MBS need to be carefully ruled out. Using spin-polarized scanning tunneling spectroscopy, Jeon <jats:italic>et al.</jats:italic> studied chains of iron atoms deposited on superconducting lead and found a more distinctive signature of the topological states. Unlike trivial zero-energy states, MBS exhibited a characteristic spin-polarization signal. </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="6364" page="772" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan3670">772</jats:related-article> </jats:p>

<jats:title>Measuring the impact of the media</jats:title> <jats:p> The active participation of the people is one of the central components of a functioning democracy. King <jats:italic>et al.</jats:italic> performed a real-world randomized experiment in the United States to understand the causal effect of news stories on increasing public discussion of a specific topic (see the Policy Forum by Gentzkow). Social media posts increased by almost 20% the first day after the publication of news stories on a wide range of topics. Furthermore, the posts were relatively evenly distributed across political affiliation, gender, and region of the United States. </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="6364" page="776" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao1100">776</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6364" page="726" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aar2579">726</jats:related-article> </jats:p>

<jats:title>Disappearance of an ice sheet</jats:title> <jats:p> The Cordilleran Ice Sheet is thought to have covered westernmost Canada until about 13,000 years ago, even though the warming and sea level rise of the last deglaciation had begun more than a thousand years earlier. This out-of-phase behavior has puzzled glaciologists because it is not clear what mechanisms could account for it. Menounos <jats:italic>et al.</jats:italic> report measurements of the ages of cirque and valley glaciers that show that much of western Canada was ice-free as early as 14,000 years ago—a finding that better agrees with the record of global ice volume (see the Perspective by Marcott and Shakun). Previous reconstructions seem not to have adequately reflected the complexity of ice sheet decay. </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="6364" page="781" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan3001">781</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6364" page="721" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aaq1179">721</jats:related-article> </jats:p>

<jats:title>Wave upon wave of disease</jats:title><jats:p>The cholera pathogen,<jats:italic>Vibrio cholerae</jats:italic>, is considered to be ubiquitous in water systems, making the design of eradication measures apparently fruitless. Nevertheless, local and global<jats:italic>Vibrio</jats:italic>populations remain distinct. Now, Weill<jats:italic>et al.</jats:italic>and Domman<jats:italic>et al.</jats:italic>show that a surprising diversity between continents has been established. Latin America and Africa bear different variants of cholera toxin with different transmission dynamics and ecological niches. The data are not consistent with the establishment of long-term reservoirs of pandemic cholera or with a relationship to climate 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="6364" page="785" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aad5901">785</jats:related-article>, p.<jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6364" page="789" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao2136">789</jats:related-article></jats:p>

<jats:title>Wave upon wave of disease</jats:title> <jats:p> The cholera pathogen, <jats:italic>Vibrio cholerae</jats:italic> , is considered to be ubiquitous in water systems, making the design of eradication measures apparently fruitless. Nevertheless, local and global <jats:italic>Vibrio</jats:italic> populations remain distinct. Now, Weill <jats:italic>et al.</jats:italic> and Domman <jats:italic>et al.</jats:italic> show that a surprising diversity between continents has been established. Latin America and Africa bear different variants of cholera toxin with different transmission dynamics and ecological niches. The data are not consistent with the establishment of long-term reservoirs of pandemic cholera or with a relationship to climate 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="6364" page="785" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aad5901">785</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6364" page="789" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao2136">789</jats:related-article> </jats:p>

<jats:title>Fly brain inspires computing algorithm</jats:title> <jats:p> Flies use an algorithmic neuronal strategy to sense and categorize odors. Dasgupta <jats:italic>et al.</jats:italic> applied insights from the fly system to come up with a solution to a computer science problem. On the basis of the algorithm that flies use to tag an odor and categorize similar ones, the authors generated a new solution to the nearest-neighbor search problem that underlies tasks such as searching for similar images on the web. </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="6364" page="793" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aam9868">793</jats:related-article> </jats:p>

<jats:title>Metabolic regulation of genome stability</jats:title> <jats:p> Cells respond to metabolic fluctuations by adjusting the speed of DNA replication as a safeguard for genome stability. Somyajit <jats:italic>et al.</jats:italic> elucidate the cellular mechanisms that align replication fork dynamics with metabolic pathways (see the Perspective by Gómez-González and Aguilera). The elevation of reactive oxygen species (ROS) levels under metabolic stress dissociates a replication accelerator from the replisome and leads to replication slowdown, thus preventing replication stress. Studying this genome surveillance mechanism in cancer cells with elevated ROS levels and increased replication adaptability may provide opportunities to specifically target tumors. </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="6364" page="797" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aao3172">797</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6364" page="722" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aaq0678">722</jats:related-article> </jats:p>

<jats:title>Taming mitosis for differentiation</jats:title> <jats:p> The mitotic oscillator consists of molecular switches known to drive cell division forward. This conserved clocklike regulatory circuit has not previously been implicated in cellular processes other than division. Multiciliated cells generate motile cilia-powered flows that are essential for brain, respiratory, and reproductive functions. Al Jord <jats:italic>et al.</jats:italic> found that the mitotic oscillator was activated in a calibrated fashion in terminally differentiating progenitors of multiciliated cells (see the Perspective by Levine and Holland). The oscillator function was used to drive massive production of cilia-nucleating centrioles while avoiding mitotic commitment. Thus, mammalian postmitotic progenitors can recruit and calibrate the mitotic oscillator to impose timing and directionality of cellular differentiation instead of proliferation. </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="6364" page="803" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan8311">803</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6364" page="716" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aaq0770">716</jats:related-article> </jats:p>

<jats:title>Regulated lysosomal efflux of amino acids</jats:title> <jats:p> A new technique allows rapid purification of lysosomes and metabolic profiling by liquid chromatography and mass spectrometry. Abu-Remaileh <jats:italic>et al.</jats:italic> engineered cultured human cells to produce a protein tag on lysosomal membranes that could be used to rapidly precipitate purified lysosomes on magnetic beads. Analysis of their contents under various conditions showed that efflux from the lysosome of most essential amino acids (but not that of most other amino acids) is a regulated process. Amino acid transport was inhibited under conditions of nutrient depletion as a result of inhibition of the mTOR (mechanistic target of rapamycin) protein kinase complex. </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="6364" page="807" related-article-type="in-this-issue" vol="358" xlink:href="10.1126/science.aan6298">807</jats:related-article> </jats:p>