Catálogo de publicaciones - revistas

<jats:title>Protein aggregation–mediated aging in yeast</jats:title> <jats:p> Old age in yeast cells results in insensitivity to mating pheromone. Reduced activity of the histone deactylase Sir2 and consequent alteration of chromatin at mating loci have been implicated in the decreased sensitivity of old cells. However, Schlissel <jats:italic>et al.</jats:italic> found a different mechanism in the yeast strains that they studied (see the Perspective by Gitler and Jarosz). Proper response to mating pheromone requires arrest of the cell cycle mediated by an RNA-binding protein, Whi3. If aggregation of Whi3 in old cells was inhibited by deletion of a glutamine-rich region that promotes aggregation, loss of sensitivity to mating pheromone was partially prevented, and replicative life span was slightly increased. </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="6330" page="1184" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aaj2103">1184</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6330" page="1126" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aam9740">1126</jats:related-article> </jats:p>

<jats:title>Putting plasmons in a spin</jats:title><jats:p>The ability of light to carry angular momentum provides an additional degree of freedom for applications such as optical tweezing and optical communication. Spektor<jats:italic>et al.</jats:italic>show that the optical angular momentum modes of light can be shrunk down to the nanometer scale through plasmonic transfer. They patterned spiral-like structures into an atomically smooth layer of gold, which allowed them to launch plasmons with controlled amounts of angular momentum.</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="6330" page="1187" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aaj1699">1187</jats:related-article></jats:p>

<jats:title>Calorimetry reaches an atomic junction</jats:title> <jats:p> Electrical and thermal conductivity in metals are linked at the macroscopic length scale because electrons carry both heat and current. Cui <jats:italic>et al.</jats:italic> found that this relationship, the Wiedemann-Franz law, holds down to the atomic scale in gold and platinum (see the Perspective by Segal). They made thermal and electrical conductance measurements through a point contact only one atom thick. In gold, the thermal and electrical conductance was quantized, owing to the electronic band structure of the metal. The experiments pave the way for high-resolution calorimetry and other thermal measurements at the nanoscale. </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="6330" page="1192" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aam6622">1192</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6330" page="1125" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aam9362">1125</jats:related-article> </jats:p>

<jats:title>Heavy hydrogen gets frozen in place</jats:title> <jats:p> Hydrogen embrittlement contributes to the failure of steel in a wide variety of everyday applications. Various strategies to mitigate hydrogen embrittlement, such as adding carbides into the steel, are hard to validate because we are unable to map the hydrogen atoms. Chen <jats:italic>et al.</jats:italic> combined fluxing steel samples with deuterium and a cryogenic transfer protocol to minimize hydrogen diffusion, allowing for detailed structural analysis (see the Perspective by Cairney). Their findings revealed hydrogen trapped in the cores of the carbide precipitates. The technique will be applicable to a wide range of problems, including corrosion, catalysis, and hydrogen storage. </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="6330" page="1196" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aal2418">1196</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6330" page="1128" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aam8616">1128</jats:related-article> </jats:p>

<jats:title>Archean cratons get a Hadean mash-up</jats:title> <jats:p>The vast majority of the rock record over Earth's 4.6-billion-year history has been destroyed through subduction and recycling back into the mantle. Although some slivers of 4-billion-year-old crust remain in the rock record, only isolated zircon mineral grains are dated to be older. However, O'Neil and Carlson found isotopic evidence of reworked basaltic crust more than 4.3 billion years old mixed into some of the 2.7-billion-year-old rocks of the Superior Province in Canada. Thus, our planet's oldest crust was reworked and retained during formation of at least one continental craton.</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="6330" page="1199" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aah3823">1199</jats:related-article> </jats:p>

<jats:title>Lifting off gold films</jats:title> <jats:p> A method for growing and removing single-crystal gold films can be used to create a flexible and transparent substrate for devices. Mahenderkar <jats:italic>et al.</jats:italic> grew gold films on the face of a silicon wafer and then used photoelectrochemistry to undergrow a sacrificial silicon dioxide layer. This layer allowed the gold film to be peeled off with adhesive tape. A 28-nm-thick gold foil showed a minimal increase in sheet electrical resistance after 4000 bending cycles. Flexible films of single-crystal cuprous oxide and of zinc oxide nanowires were then grown on the gold foils. </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="6330" page="1203" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aam5830">1203</jats:related-article> </jats:p>

<jats:title>Countering TB prodrug resistance</jats:title> <jats:p> The arsenal of antibiotics for treating tuberculosis (TB) contains many prodrugs, such as ethionamide, which need activation by normal metabolism to release their toxic effects. Ethionamide is potentiated by small molecules. Blondiaux <jats:italic>et al.</jats:italic> screened for more potent analogs and identified a lead compound called SMARt-420. This small molecule inactivates a TetR-like repressor, EthR2, and boosts ethionamide activation. SMARt-420 successfully promoted clearance of multidrug-resistant strains of <jats:italic>Mycobacterium tuberculosis</jats:italic> from the lungs of mice. </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="6330" page="1206" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aag1006">1206</jats:related-article> </jats:p>

<jats:title>The parasite of my parasite is my friend?</jats:title> <jats:p> Virulence factors of pathogenic bacteria can be swapped by means of bacterial viruses called phages. In turn, the pathogenic bacteria are under attack by the hosts' immune responses. Diard <jats:italic>et al.</jats:italic> discovered that SopEϕ, a phage parasite of pathogenic <jats:italic>Salmonella</jats:italic> species, is encouraged to spread between bacteria by the mouse host's inflammatory responses. Conversely, mucosal vaccination against <jats:italic>Salmonella</jats:italic> reduced inflammatory responses and curbed the transfer of SopEϕ to naïve bacteria. </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="6330" page="1211" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aaf8451">1211</jats:related-article> </jats:p>

<jats:title>Making more of your stomata</jats:title> <jats:p> Stomata on grasses are made up of two guard cells and two subsidiary cells, and they perform better than stomata on broad-leaved plants, which are made up only of two guard cells. Raissig <jats:italic>et al.</jats:italic> found that the MUTE transcription factor in the wheat-like grass <jats:italic>Brachypodium</jats:italic> is a little bigger than the equivalent protein in the model broad-leaved plant <jats:italic>Arabidopsis</jats:italic> . The extension in the grass protein promotes its movement into adjacent cells, prompting them to become subsidiary cells. Mutant <jats:italic>Brachypodium</jats:italic> whose MUTE protein could not move between cells lacked stomatal subsidiary cells and grew poorly. </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="6330" page="1215" related-article-type="in-this-issue" vol="355" xlink:href="10.1126/science.aal3254">1215</jats:related-article> </jats:p>

<jats:p> Oncologists have long rested their treatment plans on three so-called "pillars"—chemotherapy, surgery, and radiation. But in recent years, scientists have been busily erecting a fourth pillar: immunotherapy. The idea of harnessing the immune system to fight cancer has already moved from the lab to the clinic, thanks to technologies such as checkpoint inhibitors and genetically engineered immune cells. <jats:list list-type="bullet"> <jats:list-item> <jats:p> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.sciencemag.org/custom-publishing/technology-features/cancer-immunotherapy-comes-age">Read the Feature (Full-Text HTML)</jats:ext-link> </jats:p> </jats:list-item> <jats:list-item> <jats:p> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.sciencemag.org/sites/default/files/custom-publishing/documents/17MarchBioengineeringFeature.pdf">Read the Feature (PDF)</jats:ext-link> </jats:p> </jats:list-item> <jats:list-item> <jats:p> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.sciencemag.org/sites/default/files/custom-publishing/douments/17MarchNewProducts.pdf">Read New Products (PDF)</jats:ext-link> </jats:p> </jats:list-item> </jats:list> </jats:p>