Catálogo de publicaciones - revistas

<jats:title>Quantum dots line up as a quasicrystal</jats:title> <jats:p> Quasicrystals have rotational symmetry but no long-range order. Although several materials have quasicrystalline order, examples of quasicrystalline superlattices formed from different types of particles are rare. Nagaoka <jats:italic>et al.</jats:italic> discovered a type of 10-fold quasicrystalline superlattice formed from truncated tetrahedral quantum dots (see the Perspective by Wu and Sun). The order is driven by a “flexible polygon tiling rule,” which explains the unique arrangement of the quantum dots. </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="6421" page="1396" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav0790">1396</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6421" page="1354" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav8597">1354</jats:related-article> </jats:p>

<jats:title>Breaking through the nitrogen ceiling</jats:title> <jats:p> Single-molecule magnets could prove useful in miniaturizing a wide variety of devices. However, their application has been severely hindered by the need to cool them to extremely low temperature using liquid helium. Guo <jats:italic>et al.</jats:italic> now report a dysprosium compound that manifests magnetic hysteresis at temperatures up to 80 kelvin. The principles applied to tuning the ligands in this complex could point the way toward future architectures with even higher temperature performance. </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="6421" page="1400" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav0652">1400</jats:related-article> </jats:p>

<jats:title>Not as advertised</jats:title> <jats:p> Marine protected areas (MPAs) have increasingly designated globally, with an associated advertised percentage of area protected. However, recent research has made it clear that many MPAs are not actually protecting marine biodiversity. Dureuil <jats:italic>et al.</jats:italic> focused on European MPAs and found that trawling, one of the most damaging types of fishing, occurs widely in these areas. Furthermore, using sharks and rays as indicator species, they found that many MPAs are failing to protect vulnerable species. </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="6421" page="1403" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau0561">1403</jats:related-article> </jats:p>

<jats:title>Rooting out the mechanism of asymmetry</jats:title> <jats:p> Plant roots grow not in response to architectural blueprints but rather in search of scarce resources in the soil. Orosa-Puente <jats:italic>et al.</jats:italic> show why a new lateral root emerges on the damp side of a root rather than the dry side (see the Perspective by Giehl and von Wirén). The transcription factor ARF7 is found across the whole root but acquires a posttranslational modification on the dry side of the root, which represses its function. ARF7 on the damp side remains functional and is thus able to initiate the signaling cascade that leads to a new lateral root. </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="6421" page="1407" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau3956">1407</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6421" page="1358" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav9375">1358</jats:related-article> </jats:p>

<jats:title>The strength of long-range ties</jats:title> <jats:p> It seems reasonable that we would have the closest, strongest ties with people in our immediate social network and that the ties between networks would be weaker. However, Park <jats:italic>et al.</jats:italic> discovered strong ties that spanned extreme network (not geographic) distances in 11 culturally diverse population-scale networks on four continents—encompassing 56 million Twitter users and 58 million mobile phone subscribers. Although they are fairly rare, strong ties between networks could be important for the spreading of ideas or disease. </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="6421" page="1410" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau9735">1410</jats:related-article> </jats:p>

<jats:title>Late Permian seed-plant evolution</jats:title> <jats:p> The great evolutionary expansion of seed plants took place in the Mesozoic era, which began after the Permian mass extinction 252 million years ago. Blomenkemper <jats:italic>et al.</jats:italic> report the discovery of seed-plant fossils from Late Permian (252-million- to 260-million-year-old) deposits on the margins of the Dead Sea in Jordan. This area represents an equatorial habitat with pronounced dry seasons. These fossils, which include the earliest records of conifers, push back the ages of several important seed-plant lineages. Some of these lineages appear to span the mass extinction event at the end of the Permian, which suggests that the communities they supported may have been more stable than expected over this transition. Thus, early evolutionary innovations can occur in drought-prone tropical habitats—which rarely offer the conditions needed for fossil preservation. </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="6421" page="1414" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aau4061">1414</jats:related-article> </jats:p>

<jats:title>Small molecules spark NK cell response</jats:title> <jats:p> Immunotherapy is a powerful treatment for certain cancers. Yet for those patients that do not respond, simultaneous strategies that mobilize the immune system and directly target malignant cells may be more effective. Ruscetti <jats:italic>et al.</jats:italic> report that combining two clinically approved cancer drugs promoted immune surveillance and killing of KRAS-mutant lung tumors in mice (see the Perspective by Cornen and Vivier). The two small molecules—a mitogen-activated protein kinase inhibitor and a cyclin-dependent kinase 4/6 inhibitor—induced natural killer (NK) cell recruitment and elimination of senescent lung cancer cells, which did not occur when either agent was used alone. </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="6421" page="1416" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aas9090">1416</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6421" page="1355" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aav7871">1355</jats:related-article> </jats:p>

<jats:title>Membrane scission by ESCRTs</jats:title> <jats:p> The ESCRT protein complexes are essential for cell division, the release of HIV from infected cells via budding, and other cell processes involving the scission of narrow membrane necks from their inner surface. The unusual inside-directed membrane cutting has made it hard to recapitulate this reaction and understand its mechanism. Schöneberg <jats:italic>et al.</jats:italic> encapsulated ESCRTs inside lipid vesicles and used optical tweezers to pull out membrane nanotubes. In the presence of adenosine triphosphate, clusters of ESCRTs generated force and constricted the nanotube, eventually severing it. This approach provides a window into the molecular mechanisms involved in the activities of ESCRTs. </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="6421" page="1423" related-article-type="in-this-issue" vol="362" xlink:href="10.1126/science.aat1839">1423</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>