Catálogo de publicaciones - revistas

<jats:title>Sticky even when wet</jats:title> <jats:p> Tissue adhesives are used as an alternative to stitches or staples and can be less damaging to the healthy tissues. But they can suffer from low biocompatibility and poor matching of the mechanical properties with the tissues. Li <jats:italic>et al.</jats:italic> combined an adhesive surface with a flexible matrix to develop an adhesive that has the right level of stick but moves with the surrounding tissues. The adhesive is effective in the presence of blood and thus might work during wound repair. </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="6349" page="378" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aah6362">378</jats:related-article> </jats:p>

<jats:title>Atomic hydrogen with an iron assist</jats:title> <jats:p> Metal polyhydrides can be used at lower pressures to make material that might have atomic hydrogen bonding. Pépin <jats:italic>et al.</jats:italic> manage to synthesize an incredibly hydrogen-rich FeH <jats:sub>5</jats:sub> compound at 130 GPa pressure. The material consists of slabs of four thin planes of atomic hydrogen intercalated with layers of quasicubic FeH <jats:sub>3</jats:sub> units. These metal polyhydrides were stable at far more accessible pressures than pure hydrogen. This achievement provides an opportunity to investigate special electrical properties expected from atomic hydrogen bonding, such as superconductivity. </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="6349" page="382" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan0961">382</jats:related-article> </jats:p>

<jats:title>Patterning without polymers</jats:title> <jats:p> Nanoscale patterning usually requires multiple steps to mask, pattern, and develop sequential layers. One overriding concern is to obtain compatibility between all the materials, as well as the patterning techniques used, to ensure accurate and clean processing. Wang <jats:italic>et al.</jats:italic> use light-responsive ligands to change the solubility of nanocrystals in specific solvents, so that development can be done by simple redispersion of nanocrystals in dark regions (see the Perspective by Striccoli). The process can fully utilize the advantages of conventional semiconductor processing, but without the need for photoresists, because the nanocrystals are only deposited where they are exposed to light. </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="6349" page="385" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan2958">385</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6349" page="353" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan8430">353</jats:related-article> </jats:p>

<jats:title>Low-temperature CO removal</jats:title> <jats:p> Carbon monoxide deactivates fuel cell catalysts, so it must be removed from H <jats:sub>2</jats:sub> generated from hydrocarbons on site. Yao <jats:italic>et al.</jats:italic> developed a catalyst composed of layered gold clusters on molybdenum carbide (MoC) nanoparticles to convert CO through its reaction with water into H <jats:sub>2</jats:sub> and CO <jats:sub>2</jats:sub> at temperatures as low as 150°C. Water was activated on MoC to form surface hydroxyl groups, which then reacted with CO adsorbed on the gold clusters. </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="6349" page="389" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aah4321">389</jats:related-article> </jats:p>

<jats:title>Iceland's molten roots</jats:title> <jats:p>Major hot spot plumes are responsible for basaltic ocean island chains such as Hawaii. Yuan and Romanowicz used seismic tomography, which constructs an x-ray–like picture of Earth's interior from seismic waves, to show that the root of Iceland's hot spot plume is partially molten. The partially molten region is located near Earth's core-mantle boundary and has been challenging to image with geophysical methods. This approach may be applicable to other hot spots with similar areas of melts or other enigmatic regions in the lower mantle.</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="6349" page="393" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan0760">393</jats:related-article> </jats:p>

<jats:title>Flat-out failure of copper films</jats:title> <jats:p> As integrated circuits shrink in size, so does their nanocrystalline metal wiring. Defects at the interfaces between crystallites (grain boundaries) can degrade wires' electrical and thermal conductivity, as well as their longevity. Using scanning tunneling microscopy, Zhang <jats:italic>et al.</jats:italic> showed that the surfaces of nanocrystalline copper films are not flat but rather have ridges and valleys created by the grains rotating out of plane, which then introduces grain boundary defects. Such defects might be avoided if films of different orientations could be grown. </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="6349" page="397" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan4797">397</jats:related-article> </jats:p>

<jats:title>The disappearance of fine motor control</jats:title> <jats:p> Manual skills are much better developed in primates than in rodents. This difference is in part due to species-specific differences in the control of motoneurons by the brain. Gu <jats:italic>et al.</jats:italic> used a range of approaches to evaluate potential corticospinal tract projections in neonatal mice. These projections exist immediately after birth but disappear within the first 2 postnatal weeks owing to the actions of plexin A, a member of the semaphorin receptor family. Targeted deletion of semaphorin receptors in mutant mice prevented elimination of corticospinal tract projection and loss of functional monosynaptic input to spinal motoneurons. </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="6349" page="400" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan3721">400</jats:related-article> </jats:p>

<jats:title>More rain means more pollution</jats:title> <jats:p> Nitrogen input from river runoff is a major cause of eutrophication in estuaries and coastal waters. This is a serious problem that is widely expected to intensify as climate change strengthens the hydrological cycle. To address the current lack of adequate analysis, Sinha <jats:italic>et al.</jats:italic> present estimates of riverine nitrogen loading for the continental United States, based on projections of precipitation derived from climate models (see the Perspective by Seitzinger and Phillips). Anticipated changes in precipitation patterns are forecast to cause large and robust increases in nitrogen fluxes by the end of the century. </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="6349" page="405" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan2409">405</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6349" page="350" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aao0812">350</jats:related-article> </jats:p>

<jats:title>Predicting responses to immunotherapy</jats:title> <jats:p> Colon cancers with loss-of-function mutations in the mismatch repair (MMR) pathway have favorable responses to PD-1 blockade immunotherapy. In a phase 2 clinical trial, Le <jats:italic>et al.</jats:italic> showed that treatment success is not just limited to colon cancer (see the Perspective by Goswami and Sharma). They found that a wide range of different cancer types with MMR deficiency also responded to PD-1 blockade. The trial included some patients with pancreatic cancer, which is one of the deadliest forms of cancer. The clinical trial is still ongoing, and around 20% of patients have so far achieved a complete response. MMR deficiency appears to be a biomarker for predicting successful treatment outcomes for several solid tumors and indicates a new therapeutic option for patients harboring MMR-deficient cancers. </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="6349" page="409" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aan6733">409</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6349" page="358" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aao1894">358</jats:related-article> </jats:p>

<jats:title>A tale of CAT tails</jats:title> <jats:p> When protein translation fails, the incomplete nascent polypeptide is targeted for degradation by the highly conserved ribosome-associated quality control complex (RQC). Mutations in RQC components lead to stress at the cellular level and neurodegeneration at the organismal level. Recent studies have shown that RQC tags partially synthesize proteins with C-terminal alanine and threonine (CAT) tails in an unusual elongation reaction. Working in yeast, Kostova <jats:italic>et al.</jats:italic> elucidated the role of this process. CAT-tailing is a fail-safe mechanism to ensure the degradation of partially synthesized proteins. The elongation process appears to “push” lysines out of the ribosome exit tunnel, which allows them to be marked by ubiquitin degradation signals. </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="6349" page="414" related-article-type="in-this-issue" vol="357" xlink:href="10.1126/science.aam7787">414</jats:related-article> </jats:p>